Side by side

Seiko Prospex SeavsYema Superman Slim CMM.20

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

Prospex Sea
SeikoProspex Sea
MSRP $1,500
Superman Slim CMM.20
YemaSuperman Slim CMM.20
MSRP $2,372
What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

Seiko Prospex Sea

Seiko Prospex Sea owners and reviewers praise its Marinemaster-style aesthetic, excellent case finishing, and impressive LumiBrite lume. The watch is powered by the 6R15 movement with a 50-hour power reserve and comes with both a steel bracelet and a silicone strap. Some owners find the Seiko Prospex Sea to be a great value and a suitable first "proper" watch, while others report it is uncomfortably big, thick, and heavy on smaller wrists. Reviewers note the GMT function is secondary with a less prominent scale, and the bezel's quieter clicks may not appeal to all. On balance, owners and reviewers rate the Seiko Prospex Sea highly for its classic design and finishing at its price point.

Yema Superman Slim CMM.20

Owners and reviewers praise the Yema Superman Slim CMM.20 for its appealing retro design, balanced 39mm case, and in-house CMM.20 micro-rotor movement, with some finding the fish scale bracelet attractive. Concerns exist regarding its $2500/€2,490 MSRP, with some owners questioning its value and noting the potential for QC issues or a "jittery" seconds hand attributed to the new movement. The bracelet's articulation and stamped clasp draw criticism, though some owners report it improves with wear. Overall, owners and reviewers appreciate the Yema Superman Slim CMM.20's vintage styling and unique micro-rotor movement, but its value proposition and some finishing details are points of contention.

At a glance

13 of 29 specs differ
Diameter
Prospex Sea43.5mm
Superman Slim CMM.2039mm
Power Reserve
Prospex Sea70h
Superman Slim CMM.2040h
Water Resistance
Prospex Sea200m
Superman Slim CMM.20300m
MSRP
Prospex Sea$1,500
Superman Slim CMM.20$2,372

Full specifications

Case

6 specs
Diameter
43.5mm
39mm
Thickness
13.3mm
9.95mm
Lug-to-Lug
51mm
Lug Width
22mm
20mm
Material
Titanium
316L Stainless Steel
Water Resistance
200m
300m

Crystal & Dial

3 specs
Crystal
Sapphire
Domed Sapphire
AR Coating
Anti-reflective coating on inner surface
Inner
Lume
LumiBrite on hands and index(es)
None

Movement

3 specs
Caliber
6R35
Yema CMM.20
Power Reserve
70h
40h
Jewels
24
25

Pricing

1 specs
MSRP
$1,500
$2,372
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