Bremont Supermarine 300MvsSeiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition
The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.
At a glance
13 of 29 specs differFull specifications
Case
5 specsCrystal & Dial
4 specsMovement
3 specsPricing
1 specsFollow this matchup
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Owners + reviewers, side by side
Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.
The Bremont Supermarine 300M is praised for its comfortable 40mm and 42mm case sizes, with owners noting the 42mm wears well on smaller wrists due to its lug design. One owner highlights the 13mm thinness of the 40mm case, considered compact for a 300m diver. The watch is priced at $1375. On balance, owners and reviewers appreciate the Bremont Supermarine 300M for its wearability and compact dimensions, especially for a dive watch.
The Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition is praised for its beautiful design and refinement over previous models, featuring vertically textured glacier-inspired dials. Owners, however, consider the €1500 RRP too high, suggesting a price closer to €900-€1000, noting the aluminum bezel insert instead of ceramic. Some owners report the 6R movement runs slow. On balance, owners find the Seiko Prospex Sea 1970 Heritage Diver's Save the Ocean Special Edition beautiful and a refinement, but the price and aluminum bezel are points of contention.
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