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Bella Rocket Blender 12-Piece Set vs. KOIOS Pro 850W Bullet Side-by-Side Comparison




Our Verdict
- Performance (60%)5.7/10
- Design (25%)7.8/10
- Usability (15%)8.7/10
- Performance (60%)7.1/10
- Design (25%)8.3/10
- Usability (15%)7.3/10
Both blenders are similarly priced and come with a generous set of accessories, but the KOIOS Pro 850W Bullet outperformed the Bella Rocket Blender 12-Piece Set in processing raw nuts, dried berries, and high-fiber foods. As a result, the protein shakes and fibrous mixtures the KOIOS produced had superior nutrient extraction and smoother texture compared to those from the Bella, despite the tiny chunks here and there. When it came to making the perfect smoothie, the BELLA Rocket Blender and the KOIOS Pro 850W Bullet both offered comparable performance. However, our data revealed that the Bella was slightly faster in this regard.
In terms of construction, both blenders are moderately built, but the KOIOS has a sleeker metal finish and offers more stable operation, giving it an edge over the functional yet flimsy-looking Bella. Considering all factors, we recommend the KOIOS 850W Bullet over the Bella Rocket.
Bella Rocket Blender 12-Piece Set Performance
- Protein Shake (40%)7.5/10
- Frozen Fruit Smoothie (30%)9.0/10
- Fibrous Greens (20%)0/10
- Crushed Ice (10%)0/10
- Protein Shake (40%)9.2/10
- Frozen Fruit Smoothie (30%)8.0/10
- Fibrous Greens (20%)5.0/10
- Crushed Ice Cubes (10%)0/10
Protein Shake
- Blending Time: 1 mins 30 seconds
- Result: Smooth
In this test, the BELLA blender produced a nearly perfect protein shake in one minute and thirty seconds. There was a small smattering of partially intact berries and almonds found after straining, but the oatmeal was mostly blended well so this didn’t detract much from the overall quality of the drink. With a little bit of tweaking by letting it blend longer or soak the nuts prior to use, we would even get a chunk-free consistency. You’ll find lots of personal blenders in this class, but rarely of them might provide as smooth and quick results. Some took up to four minutes to liquify oatmeal entirely, while others' blades were too weak to churn through such solid fruits (for example, the Magic Bullet, the La Reveuse, and the Icucina).
- Blending Time: 56 seconds
- Result: Smooth
The KOIOS’s blade has a rotation speed that is fairly quick for the class so it shouldn’t be surprising that this blender can make a good breakfast or post-workout milkshake in a matter of seconds. Not to mention its high-powered motor and more-than-average number of blade prongs (more prongs means more food contact, and results in faster results).
In this test, it took less than 1 minute to break down and combine all the ingredients, which was faster than most. The powerful motor couldn’t quite remove all lumps from the protein shake, but only a few chunks remained unblended, so our drink was still pleasant to drink. Moreover, the residual solids didn’t affect the tasting experience much — they were so tiny that they didn’t bother us at all. If you want smoother results, consider the NutriBullet or the Ninja Fit, though.
Frozen Fruit Smoothie
- Blending Time: 1 min 10 seconds
- Result: Silky Smooth
- Suction:
The BELLA is a classic example of why a cheaper blender isn't always worse because its smoothie-making capability proved to be even on par with those of higher-powered models, namely the Nutri Ninja Auto-iQ. This can be attributed to several factors, including blade design, motor strength, and blending speed.
The sturdy blade spined relatively fast. Working with a 240-watt motor, it took only one minute and ten seconds to blend and mix all the ingredients together. A very quick blending time for this class of blender, this speed is crucial when it comes to blending frozen ingredients as it helps to preserve the ice-cream-like texture that people look for in frozen fruit smoothies.
For the smoothie’s consistency, while there were still small bits of raspberry skin and strawberry seeds present, this is to be expected when blending ingredients of this nature. Overall, these small bits didn’t impair the smoothie’s quality at all.
- Blending Time: 1 min 20 seconds
- Result: Silky Smooth
- Suction:
The KOIOS Bullet brought all the ingredients together for a great-tasting smoothie in one minute and twenty seconds. Of all the similarly-priced blenders we tested, it was the only one that could liquify frozen ingredients that quickly. Most were 20-40 seconds slower, such as the Black+Decker, but that can make a difference; frozen foods thaw quickly at room temperature, so the longer you blend, the more your smoothie will be diluted.
Simply put, the quicker performance of the KOIOS made for a thicker and more ice-cream-like smoothie. Chilly and fresh enough to quench our thirst, it also retained the texture that people look for in frozen fruit smoothies.
Fibrous Greens
- Blending Time: 20 seconds
- Result: Failed
Upon conducting a 20-second blending cycle, we found the BELLA couldn’t perform up to its usual standards being somewhat suboptimal in processing high-fiber foods, including kale, celery, and spinach. Strain analysis of the mixture revealed a substantial volume of greens remaining partially unblended which led to a grainy texture and an inadequate extraction of the green’s nutrients, in the end.
On the contrary, some other blenders, like the Ninja Fit and the Ninja BN401, produced a smoother outcome with a significantly smaller volume of visible flakes. As such, our conclusion is that your BELLA is not well equipped to handle high-fiber foods and may fall short of the desired performance criteria for such applications.
- Blending Time: 20 seconds
- Result: Very Coarse
We evaluated how well this blender handled fiber by blending kale, celery, spinach, and water for 20 seconds. The mixture came out grainy with a substantial amount of partially blended particles. Then, we drained it through a mesh strainer and examined the pulp. It looked like green sand with a moderately coarse consistency. We didn't taste the mixture prior to draining, but this coarseness, together with the volume of pulp, meant this blender failed to extract most of the flavor from the greens.
We can’t say for sure if more blending time would improve the final result, but can conclusively say that 20 seconds worth of blending is not enough. By comparison, the Ninja Fit did the same job much better, leaving behind a significantly smaller amount of visible flakes.
Our conclusion is that the KOIOS is just mediocre for blending leafy veggies. If you want to avoid leafy chunks in a quick high-fiber beverage, this is not the blender for you.
Crushed Ice
- Ice Fineness: Coarse
- Unblended Ice: 79% of 6 oz
The BELLA appeared to lack the necessary strength for such a tough application. As a result, all the ice cubes remained virtually intact despite its significant effort. To be fair, though, this is a common limitation among personal blenders. Should you desire crushed ice with a fluffy, snow-like consistency or intend to incorporate more ice into your smoothies, consider the NutriBullet or anything with at least a 700-watt motor.
- Ice Fineness: Coarse
- Unblended Ice: 77% of 6 oz
In this test, its performance was lackluster. The machine itself is incapable of crushing ice cubes. In fact, attempting to do so is not a good idea; the heavy-duty task can take a toll on your device and impair its performance in more ordinary blends.
Bella 14-oz Rocket Blender Design
- Blade (20%)6.5/10
- Build Quality (60%)7.5/10
- Blending Cup (20%)10/10
- Blades (20%)7.5/10
- Build Quality (60%)8.0/10
- Blending Cup (20%)10/10
In the Box of the Bella Rocket Blender 12-Piece Set
- Motor base
- Two blade assemblies
- Three blending cups
- Two storage lids
- Two lip rings
- Two shaker lids
- Recipe book & user guide
- Motor Base
- Two Blade Assemblies
- Four Lids
- Cleaning Brush
- Three Blending Cups
- Recipe book & user guide
Dimensions
- Height:11.8" (30.0 cm)
- Width:4.5" (11.4 cm)
- Weight:2.3 oz (65 g)
- Shaft Length:
- Height:12.2" (31.0 cm)
- Width:5.5" (14.0 cm)
- Weight:2.9 oz (82 g)
- Shaft Length:
The KOIOS Bullet’s dimensions are about as standard as they come. At 12 inches tall by 5.5 inches wide, it is a typical size for a personal blender and can easily tuck away in your cabinet. Mobility is also very practical thanks to its compact form.
Build Quality
The motor’s build quality is on par with its price point, with a predominantly plastic housing reinforced by a thin metal layer on the outside. It doesn’t have any glaring flaws in finish, but we'd like things to be a bit sleeker, especially the outside. The same goes for the two blade assemblies. We're just less pleased with the blending cups since they both look less as quality, and feel more susceptible to damage.
Build quality is moderate, with a body mostly made of plastic. The stainless steel blades look promising in terms of durability and capability while the motor base is rather flimsy. However, despite that, this blender stands very firmly during operation. It doesn’t jump around while handling solid foods like most mid-range counterparts such as the Magic Bullet.
We like the metal surface on the front of the motor base. It gives our blender a more attractive appearance and better quality feel. After a couple of months in the lab, this surface still retains its original shine — even after the occasional cleaning with a metal scouring pad.
Blade
- Material:Stainless Steel
- Type:Sharp and Dull Blades
- Guard Material:
- Blade Count:4
- Removable:No
- Dishwasher Safe:Yes
The set includes two blade assemblies: a cross blade and a flat blade. Both pieces have average quality and lack a refined appearance. The cross blade features four prongs, potentially resulting in faster and smoother blending of wet ingredients compared to two-pronged blades. The flat blade, also known as a dry blade, is specifically designed for grinding harder ingredients such as rice, coffee beans, and whole grains.
- Material:Stainless Steel
- Type:Sharp Blade
- Guard Material:
- Blade Count:6
- Removable:Yes
- Dishwasher Safe:No
The KOIOS Bullet comes with two extractor blades: one is flat and the other shaped like a cross.
The flat blade has two dull prongs tilted slightly upwards and is only compatible with the short blending cup. We haven’t performed any tests on it, but believe this add-on will be handy for grinding hard ingredients like coffee beans, raw nuts, and whole grains. The blender’s mighty motor and consistent performance suggest it should be able to handle such ingredients.
Most of your blended treats will be best served by the cross blade. With six sharp prongs, it contacts more food at any given moment, resulting in finer outcomes and faster blending times. That being said, it looks less sturdy than some models (particularly the Ninja Fit). More prongs also means you’ll have more nooks and crannies to weave in and out of when it comes to cleaning.
Bella Rocket Blender Motor Base
- Rated Voltage:120V
- Rated Power:240 Watt
- Working Time:≤ 1 minute
- Protection:No
- Weight:
- Cord Length:2.3 ft (0.7 m)
- Extra Feature:Silicone feet
The motor is relatively resistant to overheating compared to similar models, but only in case you avoid operating it continuously for more than one minute at a time. If additional blending time is required, you should allow the motor to cool for up to three minutes before starting the next 1-minute interval. Otherwise, a cooling fan alone won't be sufficient to prevent your blender from getting hot.
Four rubber feet are placed underneath the motor to further enhance stability and reduce movement during operation. It also assists in providing proper ventilation for the motor.
- Rated Voltage:120 V
- Rated Power:850 Watt
- Working Time:≤ 1 minute
- Protection:No
- Weight:2.4 lbs (1.1 kg)
- Cord Length:4.1 ft (1.2 m)
- Extra Feature:suction feet, ventilation holes
The main housing of the KOIOS Bullet is made from medium-grade plastic, except for the front surface. It is a little smaller than other personal blenders, but could surprisingly tackle our tests without slipping or rocking around on the counter thanks to the four rubber feet at the bottom.
Most models around this price cannot run continuously for more than one minute because the motor can overheat. The KOIOS Bullet is not an exception despite the fact that it’s equipped with many ventilation holes for better heat dissipation. If your drinks demand a longer blending time, make sure you let your machine cool down for 20-30 seconds after each 1-minute interval.
Blending Cup
- Material:Plastic
- Capacity:13.5 oz, 13.5 oz, and 6 oz
- Weight:
- Dishwasher Safe:Yes
- Measurement:No
- Suitable For:Small batches
- Accessories:Two storage lid, two lip rings, two shaker Lid
This set includes three blending cups, two of which are 13.6 oz and one that is 6 oz. The two blending assemblies work interchangeably with all cups, making it very convenient to switch between different blending needs. The smaller cup is recommended for dry blends, as it comes with sieve lids that allow it to function as a shaker for ground spices and seasonings. There are also two storage lids and two removable lip rings included so you’ll find it easier to sip your drink straight from the tall cup.
- Material:Plastic
- Capacity:10 oz, 17 oz, and 17 oz
- Weight:0.2 lb, 0.23 lb, and 0.34 lb
- Dishwasher Safe:Yes
- Measurement:No
- Suitable For:Small batches
- Accessories:two spout lids, one flat-top lid, one sieve lid
In this set, there are two tall cups (17 oz) for blending watery mixtures and a short cup (10 oz) for grinding solid ingredients. The tall cups can be sealed tightly by either a flat-top lid or spout lid if you want to enjoy your drink on the go. And the short cup’s distinctive design looks lovely. It features a flat foot for increased stability and is particularly compatible with the sieve lid so you can use it as a shaker for ground spices like nutmeg, cinnamon, cocoa flour, ground coffee beans, or whatever seasonings you need.
Speed and Controls of the Bella 12-Piece Rocket Blender
- Control Type:Twist
- Min Speed:N/A
- Max Speed:N/A
- Presets:No
- Noise Level:96 (db)
- Digital Display:No
- Pulse Mode:No
The BELLA is a single speed design and doesn’t have a pulse function. This may make it difficult to control the consistency of blends, but is convenient for those who prefer a straightforward blending experience.
- Control Type:Push
- Min Speed:N/A
- Max Speed:N/A
- Presets:No
- Noise Level:97 dB
- Digital Display:No
- Pulse Mode:No
Like many personal blenders, the KOIOS offers only one speed option but doesn’t have buttons or any sort of controls. To blend, you simply press the cup down into the base, then hold it continuously until your smoothie is ready. The operating method is so simple that you may not need any practice. It’s easy to get comfortable with this blender.
Bella Rocket Blender 12-Piece Set Usability Review
- Hands-Free Operation (60%)8.6/10
- Assembly (20%)9.0/10
- Cleanability (20%)8.5/10
- Hands-Free Operation (60%)5.7/10
- Assembly (20%)10/10
- Cleanability (20%)9.5/10
Hands-Free Operation
The BELLA personal blender boasts a convenient hands-free feature, which enables blending once the cup is locked in place, eliminating the need to continuously hold the cup and activate the motor. However, it may struggle with heavy-duty tasks as it can't draw ingredients towards the blade on its own. During the smoothie test, there were brief pauses every 20 seconds to shake the cup as the frozen fruits got stuck under the blade and caused jamming. This is a common issue among personal blenders and wouldn't pose a significant problem if one is willing to spend an extra minute or two in the kitchen. In fact, some other models tested required multiple shakes to achieve a smooth blend.
You can’t walk away while the KOIOS Bullet does its job the way you might with a full-sized blender. It requires you to keep a hand on it the whole time. Plus, you may occasionally need to pause to remove the cup and give it a thorough shake.
Particularly in the smoothie test, frozen fruits got stuck under the blade and jammed it up. To even out the blend, we had to shake the cup after every 20 blending seconds. It gave us a good smoothie in 1 minute 20 seconds worth of runtime, so the process demanded four intervals total. Reviewers make a fuss about the repeated delays, but they’re a common occurrence among personal-size blenders. As long as you’re willing to spend an extra minute or two in the kitchen, it shouldn’t be a big deal.
Assembly
The BELLA is designed for easy assembly, with clear and concise instructions included. To put all the components together, just screw the blade assembly to the blending cup, insert it into the motor, and then make a quick clockwise turn to lock it in place for blending starting. Some people might find it’s a little bit frustrating to secure the blade assembly to the cup, but most of them would get the hang of it after a few tries.
Setting up this blender is a breeze. After twisting the blade assembly onto the cup, you’ll need to flip the cup over and place it securely onto the motor base, aligning the cup’s protrusions with the grooves inside the motor base. To start blending, gently push the cup down as long as you desire. Once finished, release the cup from the motor base and unscrew the blade assembly.
Cleanability
Except for the motor body, all the pieces are safe to put in the dishwasher, though we decided to clean them by hand and noticed that part of the cleaning process was performed with ease, as any remaining residues of the cups and lids are removed simply by wiping the surface with a damp soapy cloth.
The blades, on the other hand, required more attention due to their intricate design and close proximity to the assembly’s surface. As such, we had to use a straw-cleaning brush so that all remnants of food or other substances can be removed entirely.
Of all the blenders we tested, the KOIOS is the only one with a blade that can be separated from its plastic base. It goes without saying, this can be a life-saver, especially since the blade assembly is not dishwasher safe.
To remove the blade attachment from the base, push the blade gear forward until it falls out. Note that these two pieces screw very tightly together through a white gasket ring so you'll have to apply a significant force, which can be a challenge if your hands are weak or in pain.
Once you’ve separated the blade attachment, plastic base, and gasket ring, they can be washed off easily with soapy water. The only parts that are tricky to clean are the blade’s undersides, but the included small brush will make life easier on you.
The other pieces, including the lids and blending cups, can be put in the dishwasher. For manual cleaning, just rinse them with soapy water.