The catch
SIHOO Doro C300 Pro V2
With so many moving parts, tuning takes time, and the 8D arms may feel overactive.
Side by side
SIHOO C300 Pro V2 vs M57: Pro V2 can adjust depth, M57’s fixed seat has to fit as it is
Quick verdict
C300 Pro V2 is for you if seat depth needs adjusting or you want its linked support as you recline. M57 is the pick if its fixed seat depth already fits and you would rather have simpler, manual lumbar adjustments. A mesh seat and a headrest come on both, so those features alone do not justify the step up.
Before you buy
Why, and what it costs you
Seat depth changes only on Pro V2
It has 1.6 inches of travel, and the selected M57 specifies no depth slider.
Where this comes from
18.5 - 16.9 = 1.6 inches. That shows how much adjustment is available. It does not mean a fit for every body height.
The catch
SIHOO M57
The mesh is firm. Shorter legs may find the fixed seat depth too long.
SIHOO Doro C300 Pro V2
- Why pick it
- The usable seat has to get shorter or longer for you
- During recline, you want the back and arms moving as a unit
- The catch
- With so many moving parts, tuning takes time, and the 8D arms may feel overactive.
SIHOO M57
- Why pick it
- Your legs are already fine with the fixed seat depth
- A simpler chair with direct lumbar controls suits you
- The catch
- The mesh is firm. Shorter legs may find the fixed seat depth too long.
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What this page compares
How SIHOO C300 Pro V2 and M57 differ in seat-depth adjustment, lumbar controls and recline, plus the limits of automatic weight sensing.
Which one fits
Pick the situations that sound like you
I need to move the point where the seat ends behind my knees
Pro V2 has a slider. With M57 the fixed depth has to fit as it is.
- SIHOO Doro C300 Pro V2
- Better fit
- SIHOO M57
- Depends
I want to position a manual lumbar pad directly
M57 specifies lumbar adjustment both vertically and horizontally.
- SIHOO Doro C300 Pro V2
- Good
- SIHOO M57
- Better fit
A 16.5-inch seat depth is what I need
The shortest depth stated for Pro V2 is 16.9 inches. M57 needs its exact fit checked.
- SIHOO Doro C300 Pro V2
- Caution
- SIHOO M57
- Depends
My weight is above the automatic sensing range
Check how Pro V2 reclines on its own, apart from its maximum load rating.
- SIHOO Doro C300 Pro V2
- Depends
- SIHOO M57
- Depends
In practice
Differences you will notice
Seat depth changes only on Pro V2
It has 1.6 inches of travel, and the selected M57 specifies no depth slider.
How we worked this out
18.5 - 16.9 = 1.6 inches. That shows how much adjustment is available. It does not mean a fit for every body height.
Nine degrees of extra recline
The published maximum goes from 126 up to 135 degrees.
How we worked this out
135 - 126 = 9 degrees. It tells you nothing about comfort or benefit while typing.
The stated range of the automatic mechanism is narrower than the load limit
The sensing claim of 40 to 100 kg works out to about 88 to 220 lb, and its upper end is under the separate 330 lb structural rating.
How we worked this out
To convert kilograms, use 2.20462 lb per kg. How automatic recline behaves outside the stated range isn't established here.
Option A
SIHOO, Black, Standard
Doro C300 Pro V2
Seat depth, 8D synchronized arms and a broader sacral-lumbar system are what this newer full-body adaptive chair from SIHOO adds.
- Best for
- An all-mesh chair that is tall, highly adjustable and has a supportive headrest
Facts we checked
- Seat depth range of 16.9 to 18.5 inches
- Standard equipment includes eight-dimensional synchronized arms and an ultra-wide 3D headrest
- Official specifications give a 330 lb limit and 105, 120 and 135 degree recline positions
Option B
SIHOO, Black
M57
This budget all-mesh chair has been around a long time. It offers adjustable lumbar, 3D arms, a headrest and a deeper recline.
- Best for
- Medium to taller users who want airflow and head support on a budget
Facts we checked
- Arms with three-dimensional adjustment move up and down, front to back, and pivot
- Lumbar support can be shifted both vertically and horizontally
- A 330 lb maximum load and a 126 degree recline are listed in the official specifications
Spec by spec
Where they really differ
| Spec | SIHOO Doro C300 Pro V2 | SIHOO M57 | In practice |
|---|---|---|---|
| Seat depth | 16.9 to 18.5 inches | Fixed depth | To change where the front edge meets your legs, the Pro V2 has 1.6 inches of adjustment. |
| Lumbar approach | Linked sacral-lumbar support | Manual height and depth adjustment | Decide between support that follows your movement and a pad you place more directly. |
| Arms | 8D synchronized system | 3D adjustment | Look at the movements you need, and do not treat the marketing count as a comfort score. |
| Maximum recline | 135 degrees | 126 degrees | Pro V2 reclines 9 degrees further, and that counts more for breaks than for keyboard work. |
| Weight limit | 330 lb | 330 lb | Moving up to the higher-tier model leaves the published structural limit unchanged. |
Trade-offs
What each pick costs you
With SIHOO Doro C300 Pro V2
- At the time of review, the official US standard version was backordered. On the exact Amazon page, availability depended on the offer.
With SIHOO M57
- Premium commercial chairs do better on build refinement, caster quality and warranty depth.
Decision guide
How to decide
If fixed depth does cause a fit problem, the seat slider is worth paying for. If not, ask whether linked movement would improve your routine.
Seat depth is the upgrade that counts
With an adjustable seat you can move the front edge and keep your back in contact. The Pro V2's published range is 16.9 to 18.5 inches. Suppose you already know a 16.5-inch seat fits you best. Then even its shortest setting calls for caution, because extra adjustments cannot make up for a range that misses your body.
Automatic recline and maximum load make separate claims
SIHOO states that the Pro V2's weight-sensing mechanism covers 40 to 100 kg, and separately that the chair's maximum load is 330 lb. These figures describe different things. Staying under the structural limit does not prove the automatic recline will feel right. If your weight falls outside the stated sensing range, confirm how the recline behaves and what the return terms are. Do not assume the larger load number settles the question.
The simpler chair may be the more predictable pick
On M57 you move the lumbar support yourself, and the adjustment system as a whole stays fairly straightforward. Someone who wants to set a chair once and come back to it may like that. The Pro V2 has a more involved linked mechanism. When you judge it, look at how those moving parts support your usual working position as well as how far the chair reclines.
What this page can’t tell you
- Use chair dimensions and load ratings to screen options. They are not medical advice and they do not guarantee comfort.
By the numbers
What the data shows
What we found across the office chairs we compare, plus the checked facts behind each finding.
How many fit
Only 4 of the 32 models checked meet every need here: “The seat depth has to fit my legs”, “I like a suspended mesh seat”, and “I want my neck supported when I recline”.
4 models fit, out of 32 checkedShow the facts and the math
How we countedThe count uses each product's current fit ratings for “The seat depth has to fit my legs”, “I like a suspended mesh seat”, and “I want my neck supported when I recline”. A need with no documented match is not counted.
| Product | Needs it meets | Facts we checked | Sources |
|---|---|---|---|
| SIHOO Doro C300 Pro V2 |
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| SIHOO M57 |
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Ready to buy
See today’s price and what owners say
Open either model on Amazon for the current price, customer reviews and delivery options.
SIHOO Doro C300 Pro V2
The usable seat has to get shorter or longer for you
See price & reviews on AmazonSIHOO M57
Your legs are already fine with the fixed seat depth
See price & reviews on AmazonEach link opens in a new tab.
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