Formex Reef 39.5 mmvsSeiko Prospex Sea
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Measurements
Catalog photos are all shot at the same flattering size. These aren't: every case below shares one millimeter scale.
Reef 39.5 mm
Prospex Sea
Diameter
39.5mm
41.3mm
Lug-to-Lug
45.5mm
lowest
48.2mm
Thickness
11mm
lowest
12.5mm
Water Resistance
300m
300m
Power Reserve
56h
72h
highest
MSRP
$2,230
$1,100
lowest
Movement
Sellita SW300-1
Seiko 6R55
Case
4 specsCrystal & Dial
3 specsMovement
3 specsPricing
1 specsReviews
Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.
The Formex Reef 39.5 mm is widely praised for its refined finishing, improved proportions, and compelling value under €2,000. Owners and reviewers highlight its comfortable wearability on smaller wrists, unique aesthetic, and impressive specifications including 300m water resistance and a COSC-certified Sellita SW300-1 movement. Some note the 22mm lug width feels slightly disproportionate and the bracelet could benefit from more taper. A prototype crown protrusion issue is expected to be resolved in production. Overall, owners rate the Formex Reef 39.5 mm highly for its excellent build quality and tool-like features at its price point.
Owners and reviewers widely praise the Seiko Prospex Sea for its robust build quality and fair price, with many noting its comfortable silicone strap. Some owners find the watch's size, thickness, and weight to be uncomfortable for smaller wrists, while others consider the size perfect. The consensus is that the Seiko Prospex Sea offers excellent value and build quality for its price.
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