Side by side

Casio GBM-2100AvsSpinnaker Spence 300

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

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What people say

Owners + reviewers, side by side

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

Casio GBM-2100A

The premium stainless steel bezel and Bluetooth connectivity are highlighted strengths. The increased mass from the metal bezel is noted as a potential drawback for some wearers. Reviewers differ on its value proposition compared to other G-Shock models.

Spinnaker Spence 300

The Spinnaker Spence 300 is widely praised for its slim 10.9mm case and 40mm diameter, offering a comfortable and uncommon thin diver design at its price point. Reviewers and owners highlight its value, especially below $350, and its blend of retro design with modern specifications, including a 300m depth rating and a fully indexed bezel. Some owners, however, find the dial printing and bracelet finishing to be less refined, with one noting the bracelet's male end links as a drawback. The consensus is that the Spinnaker Spence 300 is highly regarded for its exceptional value and wearable dimensions, making it a strong contender for an everyday sports watch.

From video reviewers

The watch's thin 10.9mm profile for a 300m diver is a key strength. No shared weakness was identified.

At a glance

15 of 29 specs differ
Diameter
GBM-2100A44.4mm
Spence 30040mm
Power Reserve
GBM-2100A
Spence 300
Water Resistance
GBM-2100A200m
Spence 300300m
MSRP
GBM-2100A$280
Spence 300$650

Full specifications

Case

8 specs
Category
Sport
Diver
Diameter
44.4mm
40mm
Thickness
11.9mm
11.5mm
Lug-to-Lug
49.3mm
48mm
Lug Width
20mm
Material
Bio-based Resin / Stainless steel
316L Stainless Steel
Finish
Water Resistance
200m
300m

Crystal & Dial

3 specs
Crystal
Mineral
Sapphire
AR Coating
No
Dial Color
Silver
Aquamarine

Movement

3 specs
Caliber
Seiko NH35
Type
Quartz
Automatic
Power Reserve
0h

Pricing

1 specs
MSRP
$280
$650
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