Marathon JDD (Jumbo Day/Date) Anthracite Diver's AutomaticvsSeiko Prospex SPEEDTIMER Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition

Owners widely praise the Marathon JDD (Jumbo Day/Date) Anthracite Diver's Automatic as a tough, underrated tool watch with lifestyle appeal, highlighting its robust build and tritium lume for excellent legibility. However, its 46mm size is a common criticism, with some finding it heavy and top-heavy, and the OEM rubber strap stiff. One owner noted the watch runs about 10 seconds fast after three days, and the ETA 2836-2 movement offers approximately two days of power reserve. On balance, owners and reviewers rate the Marathon JDD (Jumbo Day/Date) Anthracite Diver's Automatic highly for its robust tool-watch build and legibility, despite its substantial size.

The Prospex SPEEDTIMER Seiko Brand 100th Anniversary SPEEDTIMER Limited Edition is praised for its retro design, balanced 42mm case, good finishing, and sapphire crystal. It is powered by the calibre 8R48, featuring a column wheel and vertical clutch, and offers 100m water resistance. Some find its 45-hour power reserve short compared to modern alternatives, and the date window placement is a point of discussion. The solar-powered variant is noted for its compact proportions and character, though some desire thinner cases and improved bracelet micro-adjustment. Overall, owners and reviewers appreciate the SPEEDTIMER's vintage-inspired aesthetics and solid build, with critiques focusing on power reserve and minor functional details.