Hamilton Jazzmaster Open Heart AutovsSpinnaker Spence 300
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At a glance
11 of 29 specs differFull specifications
Case
7 specsCrystal & Dial
1 specsMovement
2 specsPricing
1 specsFollow this matchup
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Owners + reviewers, side by side
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The Hamilton Jazzmaster Open Heart Auto is noted for its dressy yet versatile design, featuring striking gradient dials and intricately shaped cutouts that reveal the H-10 movement. It boasts an 80-hour power reserve and Nivachron hairspring. The watch is available in 36mm, 40mm, or 42mm stainless steel cases. On balance, the Hamilton Jazzmaster Open Heart Auto is appreciated for its visually engaging dial and movement display at its price point.
The smoked dial's precision cutouts offer a captivating view of the automatic movement. Legibility is compromised by the open-heart design.
The Spinnaker Spence 300 is widely praised for its slim 10.9mm case and 40mm diameter, offering a comfortable and uncommon thin diver design at its price point. Reviewers and owners highlight its value, especially below $350, and its blend of retro design with modern specifications, including a 300m depth rating and a fully indexed bezel. Some owners, however, find the dial printing and bracelet finishing to be less refined, with one noting the bracelet's male end links as a drawback. The consensus is that the Spinnaker Spence 300 is highly regarded for its exceptional value and wearable dimensions, making it a strong contender for an everyday sports watch.
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