Side by side

CWC G40 Sonar Quartz WatchvsGrand Seiko SBGR321

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

G40 Sonar Quartz Watch
CWCG40 Sonar Quartz Watch
MSRP $333
SBGR321
Grand SeikoSBGR321
MSRP $5,200
What people say

Owners + reviewers, side by side

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

CWC G40 Sonar Quartz Watch

Owners widely appreciate the CWC G40 Sonar Quartz Watch for its classic G10 design, 40mm case size, and 20atm water resistance, noting its light, rugged, and reliable "grab-n-go" nature. Some find the dial proportions have too much negative space, while others praise its unique anodized red crown and quality NATO straps. A larger crown can dig into the wrist, and the lack of a battery hatch is a trade-off for its 100m water resistance. On balance, owners value the CWC G40 Sonar Quartz Watch for its robust build and classic aesthetic, though its price point and competition are frequently cited concerns.

Grand Seiko SBGR321

Grand Seiko SBGR321 owners and reviewers widely praise its attractive design, compelling dimensions, and robust movement. The watch features sharp case lines with contrasting brushing and polishing, a 40mm steel case that provides presence without bulk, and 100m water resistance. Its sunburst blue dial, inspired by the dawn sky over Mount Iwate, showcases Grand Seiko's signature finishing on applied markers and hands, with a red-tipped seconds hand. The 9S65 automatic movement is noted for its precision, running within specifications, with one source reporting a +5 to -3 seconds a day rate and a 3-day power reserve. A blue rotor with a crimson rim, also inspired by Mount Iwate, is visible through the display caseback. On balance, owners and reviewers rate the Grand Seiko SBGR321 highly for its exceptional finishing and compelling blue dial design at its price point.

At a glance

9 of 29 specs differ
Diameter
G40 Sonar Quartz Watch40mm
SBGR32140mm
Power Reserve
G40 Sonar Quartz Watch40h
SBGR32172h
Water Resistance
G40 Sonar Quartz Watch200m
SBGR321100m
MSRP
G40 Sonar Quartz Watch$333
SBGR321$5,200

Full specifications

Case

4 specs
Category
Field
Dress
Thickness
12mm
13mm
Lug-to-Lug
46mm
46.6mm
Water Resistance
200m
100m

Crystal & Dial

2 specs
Dial Color
CWC G40 Sonar Quartz Watch
Black
Lume
Super-LumiNova
None

Movement

2 specs
Caliber
9S65
Power Reserve
40h
72h

Pricing

1 specs
MSRP
$333
$5,200
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