Zwilling 4-Stage vs. Longzon 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
Zwilling Manual Knife Sharpener Review
Longzon 4-stage Manual Knife Sharpener Review
Knife Sharpener type
manual
manual
Power
0W
0W

Our Verdict

6.2
Overall Score
  • Performance (50%)
    4.7/10
  • Design (15%)
    7.5/10
  • Ease of Use (35%)
    7.8/10
7.0
Overall Score
  • Performance (50%)
    5.6/10
  • Design (15%)
    9.1/10
  • Ease of Use (35%)
    8.2/10

The Zwilling 4-stage and the Longzon 4-stage sharpeners are well-built, robust sharpening devices, but that didn’t help them score well in our sharpening tests.

The Zwilling 4-stage has a solid body that is certainly made of high quality materials. Unfortunately, its fancy design features were not very useful in practice—its thin and narrow base did not help with balance, while the supposedly ergonomic handle proved awkward to grasp. The sharpener was also one of the slowest to show results. 

The Longzon offered better balance and ease of use during sharpening. It was gentle to the knife and created an extremely fine edge. However, the improvement in sharpness was modest compared to other sharpeners. The device took longer to achieve sharpness than most sharpeners as well. 

Between the two, the Longzon is the more acceptable choice. But there are better performers—take a look at our rating tables to find the right one for you.

Performance

4.7
Performance Scores
  • Sharpening Time to Cut a Lemon (35%)
    1.0/10
  • Maximum Sharpness Achieved (20%)
    7.0/10
  • Edge Smoothness (20%)
    7.3/10
  • Material Retention (25%)
    6.0/10
5.6
Performance Scores
  • Sharpening Time to Cut a Lemon (35%)
    1.0/10
  • Maximum Sharpness Achieved (20%)
    6.0/10
  • Edge Smoothness (20%)
    9.0/10
  • Material Retention (25%)
    9.0/10
1.0

Sharpening Time to Cut a Lemon

1.0
  • Sharpening Time: 3 minutes
  • Cutting Feel: Slightly forced

The Zwilling is, sadly, one of the slower sharpeners even among its category. It took 180 seconds to sharpen a sandpaper-destroyed knife to the lemon-cutting level, and even then, the cutting motion didn’t feel completely effortless. Three minutes may feel like nothing if you’re used to working with a whetstone, but for a convenient device like this one, one would expect a much shorter time.

  • Sharpening Time: 3 minutes 10 seconds
  • Cutting Feel: Swift and smooth

The Longzon sharpener was disappointing in this test: It took 190 seconds on average to sharpen a dull knife to the level where it can slice a lemon with ease. Three minutes doesn’t seem so long, but when you’re repeating a motion on a small device, it can feel like an eternity.

Unlike the case with the Mueller, the tungsten carbide blades on this device offer a tight and steady brace. For some reason unknown to us, the knife edge just didn’t get keen quickly enough with it.

7.0

Maximum Sharpness Achieved

6.0
  • Sharpening Time: 6 minutes
  • Sharpness Level: 8 - (Chicken breast with skin, 2 swipes)

While it failed quite miserably in the speed test, the Zwilling sharpener got decent results when given more time. The test knife passed the tomato test with flying colors and could cut through the muscle and runny skin on a fresh piece of chicken breast with two light and easy swipes. 

We tried it on beef tendon too, which it took two heavy strokes to sever. The device was marked as failed for this level, but we think its efforts would be sufficient for most food prep needs.

  • Sharpening Time: 6 minutes
  • Sharpness Level: 7 (ripe tomatoes)

We doubled the time in the lemon-cutting test and the Longzon sharpener could only up the knife sharpness by one level. It cut through a ripe tomato effortlessly, and took two forceful swipes to sever the tough skin on a chicken breast. This isn’t a bad performance, per se, but we had expected more from the sharpener as it looks so well-made.

7.3

Edge Smoothness

9.0
ZWILLING Edge Smoothness

Although the Zwilling peels a lot off the knife, we have to give it credit for the pretty edge it left. There are long and deep grooves along the edge—we could tell from the swarf alone—but overall, the edge is straight and consistent, and without visible chips or teeth. 

However, with its ceramic blades chipped after only a few uses, we’re at best skeptical about the device’s ability to maintain delivery of this edge quality.

Longzon Knife Sharpener Edge Smoothness

We couldn’t be more impressed when we saw the knife edge after sharpening with the Longzon. It’s smooth, shiny, and balanced between the two sides — common among electric sharpeners, but a rare thing to see with manual pull-through devices. We can’t quite explain the lack of chips, grains, or unfinished shavings — we didn’t need a magnifier to see them on the edge produced by its identical cousin, the Mueller. 

At any rate, if a clean, perfect edge is what you’re after in a handheld sharpener, the Longzon should be among your top choices.

6.0

Material Retention

9.0
ZWILLING Material Retention
ZWILLING Material Retention 1
  • Sharpening Time: 1 minute
  • Target Sharpness:

For the sharpness level it could achieve, the Zwilling shaves off way too much steel from the knife. We couldn’t help but shudder at the long curls of swarf coming out of the Coarse slot.

Most other devices employ ceramic rods for honing the knife, so even though this function comes in the form of blades on this sharpener, we really didn’t expect the ceramic to be so harsh on the knife edge.

Longzon Knife Sharpener Material Retention
Longzon Knife Sharpener Material Retention 1
  • Sharpening Time: 1 minute
  • Target Sharpness:

On most devices that employ tungsten carbide blades as the sharpening ‘abrasive’, the more material they remove, the quicker they work and the sharper the edge. The Longzon is not an exception. It took more than 3 minutes to produce a keen edge, so it’s not a complete surprise that it only removed a moderate amount of material from the edge in 1 minute.

Design

7.5
design Scores
  • Build Quality (75%)
    7.8/10
  • Grip (25%)
    6.5/10
9.1
design Scores
  • Build Quality (75%)
    9.1/10
  • Grip (25%)
    9.0/10

In the Box

ZWILLING In the Box
  • The Zwilling 4-stage sharpener
  • Instruction leaflet

The Zwilling 4-stage sharpener comes protected by a plastic blister pack, with a simple instruction manual. The device is solid and heavier than most others.

Longzon Knife Sharpener In the Box
  • The Longzon 4-stage knife sharpener 
  • Instruction manual
  • Protective gloves 

The Longzon sharpener comes in a nice cardboard box with lots of instructions and contact information printed on it. Then there’s a leaflet that features the instructions in five different languages. Two thin gloves are included in the package, presumably for protecting your hands during sharpening, though this is mentioned nowhere in the manual.

Dimensions

ZWILLING Dimensions
  • Length:
    9.3" (23.6 cm)
  • Width:
    1.7" (4.3 cm)
  • Height:
    3.1" (7.9 cm)
  • Weight:
    11.2 oz (318 g)

Longzon Dimensions
  • Length:
    9.3" (23.6 cm)
  • Width:
    1.8" (4.6 cm)
  • Height:
    3.1" (7.9 cm)
  • Weight:
    8.7 oz (246 g)

7.8

Build Quality

9.1
ZWILLING Build Quality

While its design leaves a lot of room for improvement, the Zwilling is overall a robust, well-built sharpener. Its body feels rigid and solid, the frame and paddings are made of high-quality materials, and every part fits together nicely, leaving no gaps. 

Unfortunately, the device’s weakness is its most critical part: the ceramic sharpening blades. 

Normally, ceramic is used to make honing rods on pull-through sharpeners, but on the Zwilling, it’s employed in the shape of rectangular sharpening blades with their own delicate edges. The chipping we found on those blades after only a few days of testing proved that this break from the norm was an error of judgment. Obviously, being hard but brittle, the ceramic blades couldn’t withstand a rough steel knife edge.

Longzon Knife Sharpener Build Quality

The Longzon sharpener has a strong build with quality materials and a robust design. Its working section, handle, and base are securely attached to each other, which helps with stability during sharpening. The design is function-oriented, but everything has a nice, flush finish. We couldn’t expect better, especially for its price.

6.5

Grip

9.0
ZWILLING Grip
ZWILLING Grip 1
  • Material:
    ABS, EVA

The Zwilling’s grip looks and feels fancier than most other devices’, but we wish the design were more simple. The thumb holder was awkward to grasp, and both of us testers couldn’t seem to align our fingers with the finger nubs. 

We also thought the space between the grip and the base to be excessive — a lower height and center of gravity would immensely improve the device’s stability.

Longzon Knife Sharpener Grip
  • Material:
    ABS, TPR

The Longzon has a nice, substantial grip. There’s plenty of space for larger hands or for those who want their gripping hand to be as far away from the knife as possible while sharpening.

The upper side of the grip is a plastic that’s very soft to the touch and has decent friction. The lower side features finger nubs for a firmer grip.

Working Section

ZWILLING Working Section
  • Levels of Sharpening:
    Sharpen, Polish
  • Abrasive:
    Ceramic blades
  • Mechanism:
    Pull through
  • Sharpening Angle:
    15 degrees, 10 degrees

The Zwilling sharpener has a long working section, covering two types of edge angle: standard and Asian. We find the alleged grind angles of 15 and 10 degrees to be surprisingly small—standard knives typically come at 18-22 degrees and Asian knives, 13 - 15 degrees. An edge angle of 10 degrees is probably more appropriate for razors than kitchen knives.

Angles aside, we like how the working section is closer to the base than the rest of the device is. This helps lower the center of gravity even only by a little, and improves the overall balance.

Longzon Knife Sharpener Working Section
  • Levels of Sharpening:
    Sharpen, Hone, Polish
  • Abrasive:
    Tungsten carbide blades, diamond rods, ceramic rods
  • Mechanism:
    Pull through
  • Sharpening Angle:
    20 degrees

The working section features one slot for scissors and three for kitchen knives. Instead of a prep slot, you start sharpening your knives with the tungsten blades and use the diamond and ceramic rods for further honing.

The whole working section is covered with stainless steel, making it easy to clean should the need arise.

Base

ZWILLING Base
ZWILLING Base 1
  • Material:
    Plastic
  • Feet Type:
    EVA pad

The Zwilling sharpener has a solid, flat base, with a high-quality anti-slip pad underneath. But this is yet another area where it suffers from bad design.

The base is long and narrow, which is not ideal for its considerable height. The pad only partially covers the base, leaving its border hanging in the air— the pad basically adds height while further reducing the already modest width. As a result, the device is very prone to rocking.

Longzon Knife Sharpener Base
Longzon Knife Sharpener Base 1
  • Material:
    ABS
  • Feet Type:
    EVA feet

The Longzon has a red ABS base that makes it look like a Louboutin shoe. It tapers from the working section downwards, but the base size is sufficient to keep the device in place. 

It boasts two flat, but effective, anti-slip pads underneath the working section and the grip.

Ease of Use

7.8
usability Scores
  • Slot Arrangement (10%)
    10/10
  • Insertion (20%)
    9.0/10
  • Pulling Through (10%)
    7.5/10
  • Stability on a Clean Surface (40%)
    7.5/10
  • Stability on a Wet and Dirty Surface (20%)
    6.0/10
8.2
usability Scores
  • Slot Arrangement (20%)
    7.0/10
  • Insertion (20%)
    9.0/10
  • Pulling Through (10%)
    8.0/10
  • Stability on a Clean Surface (40%)
    8.5/10
  • Stability on a Wet and Dirty Surface (10%)
    8.0/10
10

Slot Arrangement

7.0
ZWILLING Slot Arrangement

The Zwilling has more sharpening slots than most others, but its layout is straightforward. Half of the working section is for standard blades and the other half Asian, as indicated by the print underneath. The slots progress in the same order for each angle type, with their coarseness level printed on their sides.

A transparent plastic cover can be slid over the area you’re not working on, so it’s rare that you will misplace your knife while sharpening.

Longzon Knife Sharpener  Slot Arrangement

The Longzon’s layout of sharpening slots is identical to the Mueller, and in our experience, not ideal. We’d rather move Slot 3 (diamond rods) to the front of the row to serve as a prep slot.

Otherwise, the arrangement is simple and easy to work with — all the slots have the same grind angle and are designed for the same types of knife edge. The natural progression of coarseness (or fineness) level means you never have to pause halfway through in fear of going the wrong way.

9.0

Insertion

9.0
ZWILLING Insertion

It doesn’t have the widest slot openings, but insertion is still effortless with the Zwilling. Its lowered working section and the rather spacious grip do offer a sense of confidence and safety in this regard.

Longzon Insertion

Insertion was easy with the Longzon: Its wide slots with a neat design offer enough space for the blade to get in without obstruction. You may cut into the wall if you go too fast, but that should be rare.

7.5

Pulling Through

8.0
ZWILLING Pulling Through

The problem with abrasive blades is that sometimes they lose grip of the knife edge, letting it glide through untouched. The fact that its blades are made of ceramic instead of tungsten carbide as a typical sharpener’s would be doesn’t exempt the Zwilling from this issue. 

The thick frame around the slots, while offering great support, does obstruct the knife tip at the end as the downward force is still in place. It gets nicked from time to time, though this doesn’t affect the knife edge or sharpness.

Longzon Pulling Through

With the U-shaped plastic frame placed too close to the sharpening rods, we ended up cutting into them after almost every swipe. Even a few more millimeters would avoid this. But other than that minor annoyance, the Longzon offers a great sharpening experience. Its blades and rods provide a steady brace with decent and stable friction that’s evident in the near-perfect knife edge it creates. It’s also effortless to keep the blade straight during sharpening — we never ended up with an uneven edge, as was the case with its Mueller counterpart.

7.5

Stability on a Clean Surface

8.5
ZWILLING Stability on a Clean Surface

The Zwilling’s heavy weight (a whopping 11 ounces) and solidness couldn’t cancel out the effect of its massive height to stabilize the device. Nor did its narrow base and an even narrower anti-slip pad allow it to fare well in our test. The sharpener kept losing its balance.

Longzon Knife Sharpener Stability on a Clean Surface

Even though the base is tapered, it’s still large enough to support the sharpener. The rubber pads offer good contact areas and great friction, so the device wouldn’t slip on a countertop. We didn’t have to use excessive force to keep it steady during sharpening, just a firm grip.

6.0

Stability on a Wet and Dirty Surface

8.0
ZWILLING Stability on a Wet and Dirty Surface

The oil- and salt-tainted countertop only amplified all the design problems on the Zwilling. We could only keep it in place with excessive force on the grip, and so we highly recommend ensuring your countertop is dry and clean before using this sharpener.

Longzon Knife Sharpener Stability on a Wet and Dirty Surface

The slippery countertop wasn’t much of a challenge for the Longzon either. It did glide a bit when we intentionally used more force to sharpen, but it fared well most of the time.