Cubikook CS-T01 3-Stage vs. Mueller 4-Stage Manual Sharpener Side-by-Side Comparison

Anh Ngo
Anh Ngo
Reviewer
Nguyen Ntk
Nguyen Ntk
Visual Specialist
Reviewed
Our recommendations are made independently through research and testing following our review procedure. We may receive commissions from purchases made via our links at no additional costs to you.
Tested Using Methodology v1.1
Updated Nov 28, 2022
Tested Using Methodology v1.1
Updated Nov 28, 2022
Mueller 4-Stage Manual Knife Sharpener Review
Cubikook Manual Knife Sharpener Review
Knife Sharpener type
manual
manual
Power
0W
0W

Our Verdict

7.6
Overall Score
  • Performance (50%)
    6.7/10
  • Design (15%)
    9.1/10
  • Ease of Use (35%)
    8.3/10
8.5
Overall Score
  • Performance (50%)
    8.0/10
  • Design (15%)
    8.5/10
  • Ease of Use (35%)
    9.2/10

The Cubikook isn’t as fast as the Mueller; however, it’s the better choice if you’re  about more than just speed.

We like the Mueller’s sizable and ergonomic grip and appreciate the handy scissor slot. The Cubikook sports a more pragmatic design, with a wide base and low center of gravity that ensure stability and safety.

The two sharpeners maxed at the same level of keenness—Level 8, which is the highest achieved by a pull-through sharpener to date. The Cubikook was outspeeded to the tune of 15 seconds by the Mueller in the lemon-cutting test. On the other hand, the former was friendlier to the knife, peeling off much less material and doing a better job of polishing the edge.

If you care about the longevity of your knives, the Cubikook’s gentle sharpening approach works much better.

Performance

6.7
Performance Scores
  • Sharpening Time to Cut a Lemon (35%)
    8.8/10
  • Maximum Sharpness Achieved (20%)
    8.0/10
  • Edge Smoothness (20%)
    4.0/10
  • Material Retention (25%)
    5.0/10
8.0
Performance Scores
  • Sharpening Time to Cut a Lemon (35%)
    7.6/10
  • Maximum Sharpness Achieved (20%)
    8.0/10
  • Edge Smoothness (20%)
    8.7/10
  • Material Retention (25%)
    8.0/10
8.8

Sharpening Time to Cut a Lemon

7.6
  • Sharpening Time: 1 minute 15 seconds
  • Cutting Feel: Swift and smooth

The Mueller isn’t the speediest of sharpeners, but it works fast enough. We put it through the lemon test twice, and it took 60 and 90 seconds respectively to complete the task. This is quite a reasonable time range, considering how dull we made the knife before testing.

Skipping the diamond rods won’t affect the result. We only used them to rid the knife edge of metal particles and make sure it was as smooth as it could be, but if you’re in a hurry, the ceramic rods alone would suffice.

  • Sharpening Time: 1 minutes 30 seconds
  • Cutting Feel: Swift and smooth

The Cubikook does a quick job of bringing life to a dull blade. After only 90 seconds on the device, our sandpaper-destroyed test knife could cut through a lemon with one swift draw. This placed the Cubikook in the top tier of pull-through sharpeners in terms of speed.

Most kitchen knives should see improvements after about 30 seconds on the second slot.

8.0

Maximum Sharpness Achieved

8.0
  • Sharpening Time: 6 minutes
  • Sharpness Level: 8 (Chicken breast with skin, 1 swipe)

After 5 minutes on Slot 2 and 30 seconds on each of the remaining slots, our test knife was able to cut through a raw chicken breast with the skin still attached. It did need a second swipe to sever the tough, slippery fat and skin, but this is the case for most devices.

  • Sharpening Time: 6 minutes
  • Sharpness Level: 8 (Chicken breast with skin, 1 swipe)

After 6 minutes of sharpening, the test knife could cut through a fresh piece of chicken breast with the skin still on. The gristly fat under the skin kept running, but we managed to sever it with a little effort. 

We tried the knife on a piece of raw beef tendon (Level 9) and it took two forced swipes, so we decided it hadn’t progressed beyond a sharpness level of 8.

5.0

Material Retention

8.0
Mueller 4-Stage Material Retention
Mueller 4-Stage Material Retention 1
  • Sharpening Time: 1 minute
  • Target Sharpness:

The Mueller is a disappointment when it comes to preserving edge integrity. We were horrified at the size and amount of swarf the sharpener churned out after every swipe on the tungsten carbide blades. It’s all or nothing with this slot: When it works, it shaves off as much metal as it can. When it doesn’t, your knife simply glides through it, untouched.

The icing on the cake is the obvious unevenness on the two sides of the edge. We can’t quite work out the reason for this, because its sharpening slots look exactly the same as the Longzon, which created a very nice edge in our test. We re-edged the test knife and tried again, and even replaced the test knife in case it was a faulty one, but the end result was the same.

Cubikook Material Retention
Cubikook Material Retention
  • Sharpening Time: 1 minute
  • Target Sharpness:

While effective, the Cubikook doesn’t remove a lot of material. This is one of the advantages multi-stage devices have over single-stage ones such as the Sunrise Pro. The first stage (diamond-impregnated rods) helps straighten the edge before you put it through the tungsten ‘peeler’ stage. Finally, the third, ceramic stage acts as a final honing step to leave your blade as smooth as possible. 

The benefit of single-stage devices is that they sharpen your knife quicker. That’s possible because they simply pull off more metal at a time. That means your knife will get eaten up faster, so you have the choice between quick sharpening or long overall blade life.

4.0

Edge Smoothness

8.7
Mueller 4-Stage Edge Smoothness

The diamond dust and ceramic rods didn’t seem to do much if anything to smoothen the edge: It came out rough with waves and small chips all across its length. I could see it with my naked eyes and feel the chips and small particles as I ran my fingers along the edge. The discrepancy between the two sides just tops it off.

Cubikook Edge Smoothness

The Cubikook creates a smooth edge. It came out looking much better than many single-stage and even multi-stage versions like Smith’s 50264 or Chef’s Choice ProntoPro. In fact, we scored this device better on the edge smoothness test than any other we’ve tested to date. It creates the straightest line with barely any visible chips, while the grooves on the primary edge were also even and narrow.

This fine edge is the result of good design choices. The device’s working section is placed low and fastened tightly to the base, which helps distribute pressure evenly against the delicate edge regardless of how much force is applied. The ceramic rods in the final stage help remove any remaining burrs or metal particles, thus minimizing edge deformities.

Design

9.1
design Scores
  • Build Quality (75%)
    9.1/10
  • Grip (25%)
    9.0/10
8.5
design Scores
  • Build Quality (75%)
    8.8/10
  • Grip (25%)
    7.5/10

In the Box

Mueller 4-Stage In the Box
  • The Mueller 4-stage knife sharpener 
  • Instruction manual 
  • Appreciation card & promotional leaflet 

The Muller KS-4ST knife sharpener comes in a nice cardboard box. Included is a detailed user guide with safety notes and instructions on how to sharpen knives of different dullness levels.

Cubikook In the Box
  • The Cubikook sharpener
  • Thank you card 

The Cubikook comes in a nice box. Instead of an instruction booklet, the user guide is printed right on the box. We thought that was done to save paper, but then we also found a greeting card that doesn’t really say anything.

Dimensions

Mueller 4-Stage Dimensions
  • Length:
    9.3" (23.6 cm)
  • Width:
    1.8" (4.6 cm)
  • Height:
    3.1" (7.9 cm)
  • Weight:
    8.6 oz (244 g)

Cubikook Knife Sharpener Dimensions
  • Length:
    8.4" (21.3 cm)
  • Width:
    1.9" (4.8 cm)
  • Height:
    2.3" (5.8 cm)
  • Weight:
    7.9 oz (225 g)

9.1

Build Quality

8.8
Mueller 4-Stage Build Quality

The Muller sharpener appears to be made from decent-quality materials. There’s also little to complain about regarding the construction: Its parts align well and even when we dropped the device on the floor they stayed together like a one-piece tool. We don’t like its high center of gravity and prefer a more weighted base, but at the same time, we can’t deny how well it was put together.

Cubikook Knife Sharpener Build Quality

The Cubikook is easily the sturdiest handheld sharpener that we’ve tested. Its working section is secured to the base using metal screws. The device is solid, and because its parts fit together tightly, it feels like it’s one piece throughout. 

The only issue is with the label. It is a strip of silicone that’s attached to the grip with glue and is starting to fall off our one-year-old device. This, however, doesn’t affect the sharpener’s functionality.

The finish is nothing to write home about, but it does ensure easy cleanup.

9.0

Grip

7.5
Mueller 4-Stage Grip
  • Material:
    ABS plastic and rubber

The Muller has a grip that’s proportional to its wide working section. It offers lots of space for those with large hands, and there are finger nubs that make it easy to hold on to. We also appreciate the rubber padding on the upper side of the grip: It’s soft and gentle to your palm while also creating useful friction against grease or moisture.

Cubikook Knife Sharpener Grip
  • Material:
    ABS

This Cubikook’s grip is very simple. It’s a thin, flat handle with the brand label on top. 

It doesn’t have an ergonomic design or a velvety cover, but we’ve never had a problem maintaining a firm grip. However, we do think it could be even better if it were bulkier. 

The grip is connected to the base, forming a closed loop, which further improves the device’s stability. As a small plus, you can hang it on a rack or hook for quick access.

Working Section

Mueller 4-Stage Working Section
Mueller 4-Stage Working Section 1
  • Levels of Sharpening:
    Sharpen (slot 1, 2, 3), Hone (slot 4)
  • Abrasive:
    Tungsten carbide blades, diamond rods, ceramic rods
  • Mechanism:
    Pull through
  • Sharpening Angle:
    20 degree

The Muller has a large working section with one slot for scissors and three for kitchen knives. It’s placed on a rather thick base — in fact, the Muller is among the tallest of all the devices we’ve tested. Unfortunately, this is not an advantage in the world of handheld sharpeners: A high working section only makes it more prone to toppling during operation.

Cubikook Knife Sharpener Working Section
  • Levels of Sharpening:
    Coarse, Medium, Fine
  • Abrasive:
    Diamond rods, tungsten carbide blades, ceramic rods
  • Mechanism:
    Pull through
  • Sharpening Angle:
    20 degrees

The device has one slot with diamond rods that shape and straighten the edge, one with tungsten bars that remove burrs and small amounts of metal, and one with ceramic rods for honing. 

The working section is secured to the base with screws and is technically detachable. However, you’d have to remove the silicone feet before you can take it apart. Also, the manufacturer doesn’t seem to sell spare parts online. We find it a pity that the whole device has to be discarded once the abrasives wear down, even though the other parts are still in perfect condition.

Base

Mueller 4-Stage Base
  • Material:
    ABS plastic
  • Feet Type:
    Anti-slip rubber pads

The Muller has a base running from the heel of its handle to underneath its working section. The base is supported with two flat rubber pads that offer friction and keep it from sliding across the countertop during sharpening.

Cubikook Knife Sharpener Base
Cubikook Sharpener Base
  • Material:
    ABS plastic
  • Feet Type:
    silicone base

The Cubikook has a flat base with two silicone pads underneath to keep it in place. It isn’t particularly large, but because the device is modest in height and tapers at the top, the base area is more than enough to keep it from wobbling. We love that the design is simple but still very effective in ensuring stability.

Ease of Use

8.3
usability Scores
  • Slot Arrangement (10%)
    7.0/10
  • Insertion (20%)
    9.0/10
  • Pulling Through (10%)
    7.5/10
  • Stability on a Clean Surface (40%)
    8.5/10
  • Stability on a Wet and Dirty Surface (20%)
    8.0/10
9.2
usability Scores
  • Slot Arrangement (10%)
    10/10
  • Insertion (20%)
    9.5/10
  • Pulling Through (10%)
    9.0/10
  • Stability on a Clean Surface (40%)
    9.5/10
  • Stability on a Wet and Dirty Surface (20%)
    8.0/10
7.0

Slot Arrangement

10
Mueller 4-Stage Slot Arrangement

Unlike many other sharpeners where the diamond rods serve as a “prep” stage, on the Mueller, you start sharpening your knife with the tungsten carbide blades (Slot 2), then move on to the diamond rods (Slot 3) and finish on the ceramic rods (Slot 4). Interestingly, in the Amazon product description, slots 2 and 3 are swapped. 

The tungsten carbide blades remove the most material from the knife, so it makes sense that they’re the ‘coarsest’ stage. However, we found that the diamond and ceramic rods may sometimes dullen a keen edge, especially when you use both of them to ‘polish’ it. As a result, we prefer the more common setting of starting with the diamond rods for the straightening effect.

Cubikook Knife Sharpener Slot Arrangement

With one single working angle and the coarseness printed at each slot, the Cubikook Chef’ Sharpener is intuitive. Swipe through the slots until the knife is sharp — you really can’t go wrong with it. The slot labels are only embossed on one side, suggesting a right-handed orientation, but it functions just as well for southpaws. You just need to remember which slot is which.

9.0

Insertion

9.5
Mueller 4-Stage Insertion

With a long grip and a wide working section, blade insertion into the sharpening slots was effortless and didn’t require much caution. If you’ve been sharpening with mini-size devices such as the KitchenIQ, where you’re gripping right next to the sharpening slot, you will likely notice the lack of stress when working with the Mueller.

Cubikook Knife Sharpener Insertion

The Cubikook has some of the widest slot openings out of all the devices we tested. Granted, you can still cut into the walls if you have trembling hands or try to insert the blade too fast, but overall, insertion is pretty effortless and doesn’t require much concentration.

7.5

Pulling Through

9.0
Mueller 4-Stage Pulling Through

The test knife went through the last two sharpening slots with little problem. However, our experience with the coarse slot seemed to be hit-and-miss:  Sometimes, the tungsten carbide blades were almost slippery with no friction or pressure felt, which means they weren’t doing their job. Other times, they were tight and ended up removing too much material from the knife.

Cubikook Knife Sharpener Pulling Through

The Cubikook’s stability and sturdiness make pulling a blade through its slots a breeze. The smaller sharpening rods mean their cradle is rather light, but not loose — at least not when the device is still new.

Within a few months of heavy use, one of the two ceramic rods unfastened itself and started spinning whenever we pulled a blade through. This happens on both of the devices we have, so we’re not quite sure if it’s a feature or a fault in design.

We like that the sharpening slots are thin and the U-shape cutouts that frame them sit far below where the rods meet, thus staying out of the blade’s path. We can pull a whole knife through quickly, place reasonable pressure on it, even with the tip downward, and still never cut into the plastic.

8.5

Stability on a Clean Surface

9.5
Mueller 4-Stage Stability on a Clean Surface

The Muller keeps its balance well on a dry and clean wooden table or marble countertop. It’s taller than most devices, but thanks to the flat and frictious base, we never had to use excessive force to keep it in place during our multiple tests.

Cubikook Stability on a Clean Surface

The Cubikook has a low center of gravity, with its working section connected directly to its flat base. The two silicone pads underneath further aid in keeping it in place. It didn’t wobble or slip even when we deliberately applied more pressure than necessary.

8.0

Stability on a Wet and Dirty Surface

8.0
Mueller 4-Stage Stability on a Wet and Dirty Surface

We had to be a little more cautious on a messy slippery countertop, but as long as you don’t work too fast, balance and stability won’t be an issue.

Cubikook Stability on a Wet and Dirty Surface

The Cubikook stands shoulder to shoulder with the Chef’s Choice ProntoPro in this test and beats the others by leaps and bounds. It slipped but never came close to rolling or flipping. Again, a wide base and a working section placed low to its center of gravity are the recipe for success.