Side by side

Gruppo Gamma Vanguard SteelvsSeiko Prospex Sea

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

Vanguard Steel
Gruppo GammaVanguard Steel
MSRP $790
Prospex Sea
SeikoProspex Sea
MSRP $1,100

At a glance

13 of 29 specs differ
Diameter
Vanguard Steel42mm
Prospex Sea41.3mm
Power Reserve
Vanguard Steel42h
Prospex Sea72h
Water Resistance
Vanguard Steel100m
Prospex Sea300m
MSRP
Vanguard Steel$790
Prospex Sea$1,100

Full specifications

Case

6 specs
Category
Diver
Diameter
42mm
41.3mm
Thickness
12.6mm
12.5mm
Lug-to-Lug
49.5mm
48.2mm
Lug Width
22mm
20mm
Water Resistance
100m
300m

Crystal & Dial

3 specs
AR Coating
Yes
Anti-reflective coating on inner surface
Dial Color
Forged Carbon
Black
Lume
Super-LumiNova
LumiBrite on hands, index(es) and bezel

Movement

3 specs
Caliber
Miyota 9039
6R55
Power Reserve
42h
72h
Jewels
25
24

Pricing

1 specs
MSRP
$790
$1,100

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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.

Gruppo Gamma Vanguard Steel

The Gruppo Gamma Vanguard Steel is praised for its aged steel case and cream sandwich dial. However, some owners dislike the distorted sapphire crystal and the absence of minute markers, with one noting difficulty in replacing the crystal due to hand fitment. The watch features a Miyota 9039 movement with a 42-hour power reserve and an accuracy range of -10 to +30 seconds per day, and is offered with two strap options. On balance, owners value the Gruppo Gamma Vanguard Steel for its distinctive aged aesthetic and dial design, despite some reservations about the crystal.

From video reviewers

Movement accuracy is a notable strength, with one reviewer noting a -1.8 second per day deviation after initial testing. A weakness is the substantial price hike for the re-release model, which raises questions about whether the upgrades justify the cost. Reviewers disagree on the watch's originality, with one calling it "decidedly derivative" and the other not mentioning this aspect.

Seiko Prospex Sea

Seiko Prospex Sea models are widely praised for their excellent build quality, value for money, and comfortable wearability, with many appreciating the vintage-inspired designs and robust construction. Owners note the silicone straps are surprisingly comfortable and well-finished, and the Lumibrite lume is excellent. However, some find the 44.3mm size and thickness too large for smaller wrists, though others report the sizing as perfect. The 6R15 movement in some variants offers accuracy around +4 seconds per day with a 50-hour power reserve, while newer movements offer more. Some models are criticized for a bracelet width not matching the case size or a rudimentary clasp for their price point. Overall, owners and reviewers rate the Seiko Prospex Sea highly for its impressive case work and finishing at its price point.

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