Citizen Eco-Drive OnevsSeiko V739-0A50

The Citizen Eco-Drive One is widely praised for its status as the world's thinnest light-powered watch, with sources consistently citing its remarkable 2.98mm case thickness and 1mm movement. Owners and reviewers highlight its "wow factor," good build quality, and light weight due to titanium construction, with finishing compared favorably to higher-end models. The watch features a synthetic sapphire dial and a cermet bezel for protection. Some users note the absence of a seconds hand and basic functionality due to the miniaturized movement. While one source mentions a 100-day power reserve, another states it can run for 12 months on a full charge. The price is noted as $3,500 to $5,000, considered reasonable by some for the technology. However, its high price and splash-resistant water rating are seen as drawbacks by some, and a few find its aesthetic too plain, preferring other Citizen models.

Owners praise the Seiko V739-0A50 for its rare, neo-vintage appeal and excellent overall quality, noting it wears very thin and comfortably. One owner was surprised by its small 34.7mm case size. The Seiko V739 movement is Japanese-made, with the case manufactured in China. On balance, owners rate the Seiko V739-0A50 highly for its comfortable, thin wearability and excellent build quality at its price point.