alt Hacker NewsThese are fine for bike commuters, and I’ve had them before. But they are in general not fine for recreational bicyclists; these people would gladly pay a hundred dollars for a new tire to shave off three watts and are not about to add any unnecessary human-powered accessories.
An exception is bikepackers, who may prize reliability and runtime over brightness and weight. But then the dynamo we're talking about is $200-$400 and that's not including the light.