SIHOO Doro C300 vs Herman Miller Cosm High Back

Side by side from official specifications, sourced prices and User Insights. No written comparison exists for this pair yet.

SIHOO

SIHOO Doro C300

$559.99 – $569.99

Herman Miller

Herman Miller Cosm High Back

$1,925 – $2,400

9 years

longer warranty on Herman Miller Cosm High Back than SIHOO Doro C300 (official terms)

Differences at a glance

SIHOO Doro C300Herman Miller Cosm High Back

Price: $559.99 – $569.99$1,925 – $2,400
Seat height: 47–55 cm14.8–21.4 in (37.6–54.4 cm)
Seat depth: 43.5–46 cm15.9 in (40.4 cm)
Load capacity: 330 lb (≈ 150 kg)350 lb (158.8 kg)
Arms: 4D coordinated armrests (Up and down, left, right, forward and backward, tilt linkage)Leaf Arms; Height-Adjustable Arms; Fixed Arms; No Arms; Arm Height: 7.3–11.7"
Warranty: 3 years12-year, 3-shift warranty, with limited exceptions

From 1 SIHOO Doro C300 and 33 Herman Miller Cosm High Back user reviews, most mentioned first. Green is liked, orange is a caution.

Adjustability
SIHOO Doro C3007 mentions
Herman Miller Cosm High Back31 mentions
Comfort
SIHOO Doro C3004 mentions
Herman Miller Cosm High Back31 mentions
Design
SIHOO Doro C3005 mentions
Herman Miller Cosm High Back23 mentions
Recline and tilt
SIHOO Doro C3002 mentions
Herman Miller Cosm High Back19 mentions
Armrests
SIHOO Doro C3005 mentions
Herman Miller Cosm High Back12 mentions
Size and fit
SIHOO Doro C3002 mentions
Herman Miller Cosm High Back13 mentions

Which is cheaper, the SIHOO Doro C300 or the Herman Miller Cosm High Back?

The SIHOO Doro C300 is cheaper to start: $559.99 versus $1,925 for the Herman Miller Cosm High Back at the brand stores (Oct 2026).

Which has a higher weight capacity?

The Herman Miller Cosm High Back, rated for 350 lb versus 330 lb for the SIHOO Doro C300.

What do owners mention most?

Adjustability for the SIHOO Doro C300, and comfort for the Herman Miller Cosm High Back, based on review summaries.