Citizen Eco-Drive OnevsHamilton Jazzmaster Gent Quartz

The Citizen Eco-Drive One is widely celebrated for its groundbreaking thinness, with multiple sources confirming a case thickness of 2.98mm, making it the world's thinnest light-powered watch. Owners and reviewers alike praise its "wow factor," describing it as "svelte" and "beautiful" with a titanium case and bracelet that feels exceptionally light on the wrist. The Eco-Drive quartz movement offers a power reserve of up to 100 days, and its miniaturization is considered impressive. However, the price is noted as a significant barrier for some, and one owner finds its aesthetic too plain or dated. Servicing is restricted to authorized centers due to proprietary construction. Overall, owners and reviewers rate the Citizen Eco-Drive One highly for its extreme thinness and lightweight titanium construction.

Owners widely praise the Hamilton Jazzmaster Gent Quartz for its dressier, unique aesthetic, with specific admiration for the dark, iridescent dial and the machine-work on the minute markers. The 40mm size is considered suitable for smaller wrists, though lug-to-lug measurements are debated. Some owners find the open-heart dial busy and difficult to read due to silver lines resembling hands, and the skeleton version is also noted for excessive branding. The H-20-S movement in the skeleton model is thought to have a 42-hour power reserve. Overall, owners appreciate the Hamilton Jazzmaster Gent Quartz for its distinctive mid-century modern design and detailed finishing.