Formex Reef 39.5 mmvsSeiko Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition
The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.
At a glance
12 of 29 specs differFull specifications
Case
4 specsCrystal & Dial
4 specsMovement
3 specsPricing
1 specsFollow this matchup
Get a note when Formex Reef 39.5 mm vs Seiko Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition gets more votes, a community discussion, or a price drop. No account needed.
Owners + reviewers, side by side
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, comfortable and well-proportioned case design, and impressive specifications for its price point, including COSC-certified Sellita SW300-1 movement and 300m water resistance. Owners and reviewers highlight the tool-less micro-adjust clasp and quick-release spring bars as practical features. Some reviewers note that the 22mm lug width feels slightly disproportionate to the smaller case, and the bracelet could benefit from more taper, though this is a point of contention for some owners who value the overall package. A prototype crown protrusion issue is noted as being addressed for production. On balance, owners and reviewers rate the Formex Reef 39.5 mm highly for its excellent value and well-executed design.
The Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition is praised for its compact 40mm case and the new Caliber 6R55 movement offering a 72-hour power reserve. Owners and reviewers highlight the stunning dials as a strong suit for Seiko. However, the 6R movement's accuracy is a point of disappointment for some, who wish for improvements closer to other movements, though others accept it given the excellent overall package. Press images suggest the bracelet end links may appear disjointed. Overall, owners and reviewers rate the Prospex Sea Seiko Prospex 1965 Heritage Diver’s Watch Save the Ocean Limited Edition well, with the stunning dials and improved power reserve being the biggest reasons.
More watches worth a look
Matched to the watches above on size, movement, style and price — microbrands first. Open any one to dig in.
People also compared
Comparisons nearby in the catalog — alternatives to the watches above paired against the matchup.












