Marathon Steel Navigator SSNAV AutovsSeiko Prospex Sea 1968 Heritage Diver's GMT
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
6 specsCrystal & Dial
2 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 Marathon Steel Navigator SSNAV Auto is praised for its high-accuracy quartz movement, with owners noting its comfort and reliable performance. Reviewers highlight its functional tool-watch appeal, featuring a sandblasted steel case, tritium tubes for constant low-light visibility, and 100-meter water resistance. One owner finds the 41mm case runs a bit small. The Marathon Steel Navigator SSNAV Auto utilizes an ETA F06.412 quartz movement with a claimed accuracy of +/- 10 seconds per year and includes a GMT bidirectional bezel. Overall, owners and reviewers rate the Marathon Steel Navigator SSNAV Auto highly for its comfortable wear and dependable, high-accuracy quartz movement.
The Seiko Prospex Sea 1968 Heritage Diver's GMT is widely praised for its build quality, finishing, and comfortable wearability, offering good value for its price point. Owners and reviewers highlight the attractive silver/white sunray dial, blue ceramic bezel, and the premium feel of the improved bracelet clasp with excellent micro-adjustment. The Caliber 6R54 movement provides a 72-hour power reserve, and real-world accuracy often exceeds its stated range of +25 to -15 seconds per day, with some owners reporting figures around +3 to +5 seconds per day. However, the caller-style GMT functionality is a point of contention for some, who find the GMT scale difficult to read and prefer a flyer GMT at this price. Some also find the crown position at 4 o'clock undesirable, and a few note a lack of dial contrast or illegibility of the inner bezel.
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