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KOIOS 4-In-1 Immersion vs Mueller Ultra-Stick Side-by-Side Comparison

Tina Pham
Tina Pham
Reviewer
Nguyen Ntk
Nguyen Ntk
Visual Specialist
Reviewed
Tested Using Methodology v1.0
Updated Jan 18, 2023
Tested Using Methodology v1.0
Updated Jan 13, 2023
The koios 4 in 1 hand blender standing on the gray table with its accessories, including a user manual, plastic beaker, whisk attachment, food processor located above a paper carton box. The KOIOS 4-in-1 immersion blender standing on the gray table with its accessories, including a user manual, plastic beaker, whisk attachment, food processor located above a paper carton box.
The Mueller Ultra-Stick Hand Blender Set including a milk frother attachment, a whisk attachment, a motor body, a blending wand, a paper carton box, and user manuals. The Mueller Ultra-Stick Hand Blender Set including a milk frother attachment, a whisk attachment, a motor body, a blending wand, a paper carton box, and user manuals.
Blenders type
immersion
immersion

Our Verdict

8.0
Overall Score
  • Performance (50%)
    7.9/10
  • Design (20%)
    7.6/10
  • Usability (30%)
    8.3/10
7.2
Overall Score
  • Performance (50%)
    7.3/10
  • Design (20%)
    6.8/10
  • Usability (30%)
    7.4/10

The Muller Ultra-Stick is similar to the KOIOS 4-in-1 in appearance, operation, and versatility, but not as good in other aspects. It’s more awkward to use and we weren’t really comfortable during operation. Our hands felt tired every single time we used this blender for more than a single batch. 

In terms of its overall construction, it looks flimsier with substandard blades. We also felt that there was a possibility of the coupler that attaches the removal parts to the motor body being irreparably broken. 

Most importantly, the textures it produced in our tests weren’t as smooth as those of the KOIOIS.

Good Enough

KOIOS 4-in-1 Hand Blender Performance

Mueller Hand Blender Performance: Fine for the Price
7.9
Performance Scores
  • Hot Soup Purée (35%)7.5/10
  • Frozen Fruit Smoothie (30%)7.8/10
  • Mayonnaise (15%)9.8/10
  • Almond Milk (15%)7.5/10
  • Whipped Egg-Whites (5%)7.0/10
7.3
Performance Scores
  • Hot Soup Purée (35%)7.0/10
  • Frozen Fruit Smoothie (30%)7.0/10
  • Mayonnaise (15%)8.5/10
  • Almond Milk (15%)7.5/10
  • Whipped Egg-Whites (5%)7.0/10
7.5

Hot Soup Purée

7.0
Scooping a spoon of pureéd soup made by the KOIOS 800W immersion hand blender from a plastic beaker.
Scooping a spoon of pureéd soup made by the KOIOS 800W immersion hand blender from a plastic beaker.
KOIOS 4-In-1 Immersion Hot Soup
A batch of soup pureéd by the KOIOS 4-in-1 hand blender is checked for smoothness by being drained through a stainless steel mesh strainer.
  • Pureeing Time: 30 seconds
  • Result: Slightly Chunky
  • Suction: No

None of the low-range blenders we tested could yield the silkiest puree in 30 seconds, but we think the KOIOS’ results will still be acceptable to most home cooks.  In particular, the soup looked silky but when we ran it through a strainer, too many tiny bits were left behind. Nevertheless, we were still satisfied with this blender, given its consistency and smooth operation. Just in case you’re expecting for silky, restaurant-quality pureés, we recommend the Vitamix 5-speed.

The Mueller Ultra-Stick Soup Test
Scooping a spoon of pureéd soup from a full batch  in a plastic beaker made by the Mueller Ultra-Stick hand blender.
A batch of soup pureéd by the Mueller Ultra-Stick immersion blender is checked for smoothness by being drained through a stainless steel mesh strainer.
  • Pureeing Time: 30 seconds
  • Result: Slightly chunky
  • Suction: Tightly

Despite being a low-priced blender, the Mueller Ultra-Stick wasn’t any slower than the others we tested. It took about 30 seconds to yield two servings of pureed soup packed with carrots, pumpkin, and parsley.

That said, it wasn’t so good at drawing ingredients toward its blades, so we needed to move it around for an even blend. Moreover, it sucked tightly to the pot’s bottom, which didn’t cause as much spatter as the Cuisinart, but did cause small scratch marks on our cookware’s surface. It also made it very challenging for us to stir with the blending wand.

Our Mueller soup’s texture was acceptable but not the silkiest; there were still several large chunks of veggies left behind.

7.8

Frozen Fruit Smoothie

7.0
A white bowl containing a batch of green smoothie whose parts are scooped with a stainless steel spoon is between the KOIOS’s motor body and a smartphone displaying the total blending time (1 minute and 19 seconds).
A white bowl containing a batch of green smoothie whose parts are scooped with a stainless steel spoon is between the KOIOS’s motor body and a smartphone displaying the total blending time (1 minute and 19 seconds).
KOIOS 4-In-1 Immersion Smoothie
After finishing blending, the green smoothie made by the KOIOS hand blender was spread evenly throughout a white paper to check for solid chunks.
  • Blending Time: 1 min 20 secs
  • Result: Slightly Coarse
  • Suction: No

The manufacturer recommends this blender not be used to process frozen fruits. That fact made us skeptical about its overall capability. After much deliberation, we decided to stick to the initial plan, putting it through our frozen smoothie test anyway. To our surprise, its result was nearly the same as that produced by the Vitamix 5-speed immersion blender

In less than a minute and a half, it churned out a frozen smoothie that was flavorful enough to entice our taste buds. The drink didn’t have a velvety smoothness; it was a bit grainy since the kale wasn’t entirely liquified. Despite that, it was still a sweet, creamy combination that we loved to sip on.

A plastic beaker containing a batch of green smoothie whose parts are scooped with a stainless steel spoon is between the Mueller’s motor body and a smartphone displaying the total blending time (1 minute and 15 seconds).
A plastic beaker containing a batch of green smoothie whose parts are scooped with a stainless steel spoon is between the Mueller’s motor body and a smartphone displaying the total blending time (1 minute and 15 seconds).
Mueller Ultra-Stick Smoothie Test
After finishing blending, the green smoothie made by the Mueller immersion blender was spread evenly throughout a white paper to check for solid chunks.
  • Blending Time: 1 min 15 secs
  • Result: Chunky
  • Suction: Slightly

To ensure this portable machine can do the work of a full-sized blender for making smoothies, we designed this specific test for it. We would award it corresponding points if it could create a homogeneous mixture of just kale and frozen fruit. Disappointingly, we found that the Mueller Ultra-Stick isn’t great at blending solid fruit and leafy vegetables. 

In this task, it had a very hard time breaking up the ingredients. This caused it to demand up to 1 min 15 secs to finish the test. 

And although the Turbo mode is intended to give the blender ​​an extra boost at max speed, we noticed the speed increment wasn’t enough to make any difference. Our smoothie came out pretty smooth, but there were many unprocessed chunks of mango. It was also a bit grainy due to a mass of tiny leafy bits. For about $35 more, you can upgrade to the better Braun MultiQuick-5.

As this blender shouldn’t run for longer than 60 seconds at the time to avoid damage, we took a break after 30 seconds. In the meantime, we used a spatula to dislodge the food that lodged in the blade guard.

9.8

Mayonnaise

8.5
A little bit of mayonnaise sticking in the whisk attachment of the KOIOS 4-in-1 hand blender when it is removed from the full batch emulsified in a plastic beaker standing between the motor body and a smartphone displaying the total emulsion time (1 minute and 10 seconds).
A little bit of mayonnaise sticking in the whisk attachment of the KOIOS 4-in-1 hand blender when it is removed from the full batch emulsified in a plastic beaker standing between the motor body and a smartphone displaying the total emulsion time (1 minute and 10 seconds).
KOIOS 4-In-1 Immersion Mayonnaise
  • Emulsifying Time: 1 min 10 secs
  • Result: Velvety
  • Suction: No

The KOIOS made short work of incorporating egg yolks and canola oil, churning out a harmonious texture in just over one minute. Apart from being one of the fastest, it was also among the few blenders in our test that produced exceptionally smooth emulsification. Our mayonnaise came out thick, creamy, and spreadable. For such a low-priced hand blender, this performance could hardly have been better.

A white bowl of mayonnaise made by the Mueller immersion blender with a stainless steel spoon inside.
A white bowl of mayonnaise made by the Mueller immersion blender with a stainless steel spoon inside.
The whisk attachment of the Mueller is immersed in a plastic beaker containing egg yolks.
  • Emulsifying Time: 1 mins 45 secs
  • Result: Smooth
  • Suction: No

Although the Mueller’s whisk attachment has thin, floppy wires, it got the job done in less than two minutes. That was 10 seconds faster than the Braun, whose whisk is more sturdy and springy. It was nearly as fast as the high-end Vitamix and handily beat the cordless KitchenAid by a full minute.

It was also easier to clean. For the most part, its mayonnaise tailings rinsed off easily under our running tap. Using the blending shafts, on the other hand, caused the food to get clogged in the blade housing. As such, it was very challenging for us to scrub off the residuals on the blade’s backsides.

7.5

Almond Milk

7.5
The KOIOS’s motor body, a plastic beaker containing almond milk, a white plate of almond pulp, and a small red note displaying the total grinding time (1 minute 30 seconds) being side by side.
The KOIOS’s motor body, a plastic beaker containing almond milk, a white plate of almond pulp, and a small red note displaying the total grinding time (1 minute 30 seconds) being side by side.
KOIOS 4-In-1 Immersion Almond Milk
  • Grinding Time: 1 min 10 secs
  • Result: Fine
  • Suction: No

It was simple and easy to put together all the ingredients for a preservative-free milk using the KOIOS. Since this blender ground the nuts pretty evenly, our drink came out silky and creamy. That said, blending didn’t run smoothly; the blending beaker was too small, causing the liquid to overflow every time we moved the blender around.

If you intend to buy the KOIOS for drink preparation, don’t use the beaker that is included in its set.

  • Grinding Time: 1 mins 5 secs
  • Result: Coarse
  • Suction: Tightly

Grinding raw nuts shouldn’t be a challenging task for any hand blender. However, our Mueller couldn’t perform any worse, though part of the reason is due to our blending jar — its small size caused the liquid to overflow all over the countertop every single time we moved the blender. So if you intend to use this blender to prepare watery drinks, it’s best to use a bigger container. 

None of the blenders we tested could avoid suction, but the Mueller’s was so strong that it was hard to stir or withdraw the wand, and when we lifted it up the container came with it. These things caused the liquid to easily overflow.

Not only that, but this blender didn’t grind finely enough for a creamy drink. Our almond milk was drinkable, but quite watery and not as sweet as others.

7.0

Whipped Egg-Whites

7.0
The 24-oz plastic beaker containing testing beaten egg-white of the KOIOS 4-in-1 immersion blender is put upside down on the gray table with its motor body and a smartphone displaying the total whipping time (2 minutes and 41 seconds) by its sides.
The 24-oz plastic beaker containing testing beaten egg-white of the KOIOS 4-in-1 immersion blender is put upside down on the gray table with its motor body and a smartphone displaying the total whipping time (2 minutes and 41 seconds) by its sides.
KOIOS 4-In-1 Immersion Whipped Egg-Whites
  • Beating Time: 2 min 40 secs
  • Result: Stiff
  • Suction: No

The KOIOS’s whisk attachment worked well — we got the perfect meringue out of the egg whites we beat with the whisk attachment. Its metal wires are bouncy and agile, so they’re flexible enough for whipping and fluffing. However, we can’t say for sure whether those wires will hold up to thick batters for bread doughs or baked cakes. 

On a pragmatic note, the whole beating process lasted nearly 3 minutes, but it didn’t cause hand fatigue like some models, namely the Mueller Ultra-Stick or the BELLA 10-speed. We felt entirely comfortable in that prolonged operation, from start to finish. Indeed, using this blender for preparing airy, creamy desserts will help you stay creative without springing for an expensive specialty device.

Mueller Ultra-Stick Whipped Egg-Whites
Putting a plastic beaker containing beaten egg-white of the Mueller Ultra-Stick upside down on a gray table.
Inside the plastic beaker containing a batch of beaten egg-white prepared by the Mueller Ultra-Stick immersion blender.
  • Beating Time: 2 mins 37 secs
  • Result: Stiff
  • Suction: No

Before we began this test, we presumed that all the whisk attachments would perform well at  beating egg-whites, though some may be more efficient than others. Surprisingly, Mueller's performance proved us wrong.

First, it had an advantage over the blending wand in incorporating enough air into the egg whites, allowing the egg-protein to form a stiff, airy foam. What was until its motor seriously overheated several times, requiring us to let it stop and cool down. This issue didn’t regularly occur with the other blenders, and spending so long with the Mueller was tiring.

Even worse, after this test the whisk attachment had lost its original bulbous shape. The strands of looped wire were all out of their initial order, which would impair its performance in the next emulsifying and beating tasks.

Practical Simplicity

KOIOS Hand Blender Design

Mueller Ultra-Stick Hand Blender Design: Above-Average Quality
7.6
design Scores
  • Blending Shaft (30%)7.0/10
  • Build Quality (60%)7.5/10
  • Power Cord (5%)10/10
  • Beaker (5%)10/10
6.8
design Scores
  • Blending Shaft (30%)7.0/10
  • Build Quality (60%)7.0/10
  • Power Cord (5%)10/10
  • Beaker (5%)0/10

In the Box of the KOIOS Immersion Blender

In the Box of the Mueller Hand Blender
The KOIOS 4-in-1 Stick Blender is shipped with a paper carton box, an immersion blending wand, a motor body, a plastic beaker, a whisk attachment, a food processor, and a user manual.
  • Motor body 
  • Blending shaft 
  • Whisk attachment
  • Food processor
  • Beaker   
  • User manual

In addition to a blending wand, this blender also comes with a beaker, a whisk attachment, and a food processor to enhance its versatility.

The Mueller Immersion Blender milk frother attachment, motor body, blending wand, whisk attachment, paper carton box, and user manuals lying side by side on a table.
  • Motor body 
  • Blending shaft 
  • Whisk attachment
  • Milk frother  
  • User manual

Dimensions

The KOIOS 4-in Immersion Blender stands on top of its blending shaft on a gray table, with the length of the blending shaft being noted to the side as 7.9 inches, and the total length of the unit as 15.3 inches.
  • Height:
    15.3" (38.9 cm)
  • Width:
    2.1" (5.3 cm)
  • Weight:
    3.4 oz (96 g)
  • Shaft Length:
    7.9" (20.1 cm)

Like all the light-duty immersion blenders we tested, the KOIOS 4-in-1 is well balanced. It is compact, portable, and has a long blending shaft that can be immersed in even a deep pot.

The Mueller Austria Ultra-Stick Immersion Blender standing on top of its blending shaft on a gray table, with the length of the blending shaft being noted to the side as 7.7 inches, and the total length of the unit as 15.55 inches.
  • Height:
    15.6" (39.6 cm)
  • Width:
    2.8" (7.1 cm)
  • Weight:
    2.2 oz (61 g)
  • Shaft Length:
    7.7" (19.6 cm)

The Mueller Ultra-Stick has a balanced weight that makes it feel good to use. Since its blending shaft is long enough to reach the bottom of even deep pots, making hot puree soups is pretty much exactly what this machine is designed for. With this compact design, it is also very easy to tuck away in your cabinet when not in use.

7.5

Build Quality

7.0
The whisk attachment, motor body, and blending shaft of the KOIOS 4-in-1 hand-held blender lying flat on a gray table.

Made of medium-quality plastic reinforced with brushed stainless steel, the KOIOS’ body feels relatively solid (but it doesn’t look as sleek as the higher-priced models). Unlike the BELLA 10-speed, it showed no scratches after our course of testing. So far, we haven’t noticed any damage on the exterior; our blender still looks shiny and brand new.

There is a special inner rotary core fixed in the blending shaft that’s different from most immersion blenders in this price range. Thanks to this add-on, the tools are easy to attach to the motor body. Not only that, but they also latch securely in place, unlike the Muller Ultra-Stick that occasionally let go of its whisk.

A close-up of the immersion blending wand, motor body, and whisk attachment of the Mueller Stainless Steel Hand Blender.

The Mueller Ultra-Stick is mostly made of plastic reinforced with brushed stainless steel, so there is no chance of plastic’s chemicals leaching into your food. Besides being corrosion-resistant, this blender’s unique design gives it an elegant look, though it doesn’t feel as sleek as its higher-priced peers.

The blender has two buttons and a speed control knob. All seem straightforward to use, but are cheaply made. To reduce spatter-related issues, the blades are surrounded by a metal guard. We like this idea, but in our experience, this type of guard can scratch non-stick cookware.

10

Beaker

Not Included
An included plastic beaker of the KOIOS 4-in-1 hand blender standing on a gray table.
  • Material:
    Plastic
  • Capacity:
    20 oz
  • Measurements:
    Yes
  • Weight:
    0.22 lb
  • Height:
    6.7" (17.0 cm)
  • Dishwasher Safe:
    Yes
  • Tamper Included:
    No

The KOIOS’ beaker has a small 20-oz capacity with measurements in both milliliters and fluid ounces. As a nice bonus, it sports a flared base to ensure stability.

  • Material:
    N/A
  • Capacity:
    NaN fl oz (NaN ml)
  • Measurements:
    N/A
  • Weight:
    NaN oz (NaN g)
  • Height:
    NaN" (NaN cm)
  • Dishwasher Safe:
    N/A
  • Tamper Included:
    N/A

Speed and Controls of the KOIOS 800W Hand Blender

Speed and Controls of the Mueller Austria Ultra-Stick
A close-up of the Power button and the TURBO button of the KOIOS 4-in-1.
A close-up of the Power button and the TURBO button of the KOIOS 4-in-1.
A close-up of 12 speed settings on the top of the KOIOS’s motor body.
  • Control Type:
    Press-button & speed dial
  • Min Speed:
    11,500 RPM
  • Max Speed:
    14,480 RPM
  • Presets:
    No
  • Noise Level:
    90 dB
  • Digital Display:
    No
  • Pulse Mode:
    Yes

We often feel a bit awkward with blenders that control speed with top-mounted dials; it’s really challenging to move the blending wand, adjust its speed, and hold the beaker at the same time. With the KOIOS, however, that isn’t an issue.

Our 4-in-1 machine offers 12 speed options and a Turbo function. It’s all controlled using two buttons and a dial. While the front controls are extremely responsive, the dial lets us switch between various speed settings with ease and this is partly because the blender itself runs very smoothly.

In particular, throughout each of our tests, we noticed that its motor didn’t vibrate too violently. This helped reduce the overall impact on the beaker and kept it stable rather than constantly jumping around the countertop. In other words, we didn’t need to hold the beaker throughout the whole job, so it wasn’t a problem to dial in the speed with a spare hand.

However, if you find it hard to adjust the dial, you can always just hit the turbo mode. That sends the blender into its highest speed immediately.

A close-up of 8 speed settings and a speed dial of the Mueller Hand Blender.
  • Control Type:
    Press and Rotate
  • Min Speed:
    12,550 RPM
  • Max Speed:
    14,640  RPM
  • Presets:
    No
  • Noise Level:
    78 dB
  • Digital Display:
    No
  • Pulse Mode:
    Yes

The Mueller Ultra-Stick has an intuitive interface, with two buttons and an easy-to-rotate speed control knob. During operation, you can adjust the speed in eight increments by gently rotating the speed control knob. However, as we found out during our testing, there is barely a difference between the Turbo mode and the highest speed in terms of power.

7.0

Blending Shaft

7.0
The blending wand of the KOIOS 4-in-1 hand blender lying flat on a gray table.
  • Material:
    Stainless steel
  • Type:
    Sharp Blade
  • Guard Material:
    Stainless steel
  • Blade Count:
    2
  • Removable:
    Yes
  • Dishwasher Safe:
    Yes

Made of standard stainless steel plated with titanium, the blade has two prongs: one is sharp and the other is dull. Its relatively fragile construction means it isn’t intended for tough ingredients like ice cubes or coffee beans, but it’s still tough enough to handle whole-food combinations.

Unlike most other blenders with lobed or angular guards, this one’s blade guard is shaped like a parabolic arch. This special design allows us to easily reach the blade’s backside for cleaning. The vaulted slope also doesn’t trap food the way others do, so we never had to stop and dislodge debris with a spoon.

The blade guard is also designed to reduce splattering, and it’s really up to the job. However, due to its metal construction and sharp edges, it left marks on the beaker even when we blended very carefully.

A close-up of the blade assembly of the Mueller Immersion Blender.
  • Material:
    Stainless steel
  • Type:
    Sharp Blade
  • Guard Material:
    Stainless steel
  • Blade Count:
    2
  • Removable:
    No
  • Dishwasher Safe:
    Yes

The blades come relatively sharp, but they look flimsy and may dull under regular use, causing the machine to blend less efficiently. Our Mueller’s blades even slightly deformed after the frozen smoothie test.

10

Power Cord

10
The KOIOS 4-in-1 Immersion Blender on a gray table with its power cord rolled up next to it.
  • Cord Length:
    5.6 ft (1.7 m)
  • Type:
    2-prong plug
  • Detachable:
    No

The power cord is long enough that you won’t feel constrained. It has a small loop that is meant to keep the blender organized.

The Mueller Ultra-Stick Immersion Blender on a gray table with its power cord rolled up next to it.
  • Cord Length:
    4.8 ft (1.5 m)
  • Type:
    2-prong plug
  • Detachable:
    No

The power cord is long enough to easily reach our nearby outlets. Like other immersion blenders, there is no place to hide the extra cord, but it has a small loop allowing you to hang the whole blender on a hook.

Whisk Attachment

Extra Accessories

Whisk Attachment
The KOIOS 4-in-1 Immersion Blender Whisk Attachment lying flat on a gray table.
  • Material:
    Stainless steel
  • Dishwasher Safe:
    Yes
  • Removable:
    Yes

This whisk attachment is moderately good at certain tasks like beating egg whites, whipping cream, and making emulsified sauces. Compared with other low-priced hand blenders such as the BELLA 10-speed or the Hamilton, its polished stainless steel wires feel more sturdy and durable under consistent use.

The Mueller Ultra-Stick Immersion Blender Whisk Attachment lying flat on a gray table.
  • Material:
    Stainless steel
  • Dishwasher Safe:
    Yes
  • Removable:
    Yes

With the whisk attachment, your blender can be a nice replacement for a hand mixer for certain tasks, such as whipping cream, beating egg whites, and emulsifying sauces. That being said, we don’t think this additional tool can ensure high durability, given its poorly-built quality.

Food Processor

Extra Accessories

Milk Frother
The KOIOS 4-in-1 Immersion Blender Food Processor standing on a gray table.
  • Material:
    Plastic and Stainless steel
  • Dishwasher Safe:
    Yes
  • Removable:
    Yes

We haven’t conducted tests on this attachment, but the stainless steel S-blade’s construction looks capable of chopping various foods just like any other low-grade food processor.

The Mueller Ultra-Stick Immersion Blender Milk Frother Attachment lying flat on a gray table.
  • Material:
    Stainless steel
  • Dishwasher Safe:
    Yes
  • Removable:
    Yes

We haven’t performed any test on the milk frother, but we’re quite sure this attachment can make foam for your drinks. However, we suppose it will not live up to the expectations of serious latté lovers.

KOIOS Stainless Steel Hand Blender Usability Review

MuellerImmersion Blender Usability: A Little Bit Short On Blending Comfort
8.3
usability Scores
  • Ease of Use (60%)8.3/10
  • Blade Assembly (10%)8.5/10
  • Handling (20%)8.0/10
  • Cleanability (10%)8.5/10
7.4
usability Scores
  • Ease of Use (60%)7.3/10
  • Blade Assembly (10%)8.5/10
  • Handling (20%)6.5/10
  • Cleanability (10%)8.5/10
8.3

Ease of Use

7.3

This KOIOS is easier to use than many other blenders not only because of its simple design but also because its buttons are very responsive. The motor’s minimal vibration contributes to the overall usability scores as well. Since the machine itself runs very smoothly, we can maneuver the blender in comfort. It was a pleasant departure after the excessive vibration of some other blenders.

During our testing, we also found that this blender didn’t create suction — a main cause of splattering when you lift it upward for an even blend. As such, we didn’t experience any trouble when speeding up or moving the blending wand, even at the highest speed setting.

It didn’t take long for us to figure out how this blender worked. That being said, the buttons have a very awkward clicky feel. Although they’re not too stiff and demand just a light press to activate, we weren’t entirely comfortable pressing them all the way down. If you use them continuously for more than a batch, your fingertips may feel a bit tired. 

The control knob also makes the blender more complicated to use. It’s tough for one person to use the blender, adjust its speed, and hold the beaker at the same time, so we had to stop it to speed up or slow down.

8.5

Blade Assembly

8.5
The KOIOS Blade Assembly

This blender comes with accessory ejection buttons on the motor body — a handy add-on giving you more control over the blade detachment process. Just a quick press of these clicky buttons pushes the attachment off of the motor body.

Putting them back is easy as well. Simply align the shaft with the main housing and push until they click and lock into place. There is one thing we really like about this blender’s blade assembly, though: Unlike others, the KOIOS attachments do not need to be rotated to a specific alignment to lock into place.

To attach the blending wand or any blending accessories to the main body, simply line up the parts and make a quarter turn counterclockwise until you hear the unit click into place.

There is a plastic coupler that attaches the removal parts to the motor body. So far, we haven’t found any issue with this add-on. After spending several days going through hundreds of customer reviews, however, we were warned that the coupler can easily be irreparably broken.

8.0

Handling

6.5
Someone uses two hands to control the KOIOIS immersion blender: one for holding the handle and pressing the power button at the same time, the other for rotating the speed dial.

The handle was comfortable to grip in all of the tests. Together with the machine’s minimal weight, its ergonomic design helps stave off hand fatigue, even through long bouts of vigorous blending. It also helped us maintain a grip even when the surface was wet or covered in grease.

Someone uses two hands to control the Mueller Ultra-Stick immersion blender: one for holding the handle and pressing the power button at the same time, the other for rotating the speed dial.

We appreciate that the Mueller is designed with an ergonomic handle to reduce hand and wrist pain. However, because the blender itself vibrated pretty violently in all five tests, our hands got tired anyway.

8.5

Cleanability

8.5

We found the easiest and most effective way to clean the blending wand or any blending attachment was by scrubbing it under running tap water. More often than not, food tailings could be quickly removed, even when they accumulated in the blade’s backsides.

All the removable attachments are dishwasher-safe, but we recommend you wash them by hand to prevent their finish from discoloring due to abrasive dishwasher detergents. Thankfully, the manual cleaning process isn’t so difficult.

You can either scrub off the residue under the running tap or let the machine clean itself by blending it in a mixture of dish soap and water. Either method should get it perfectly clean.