There's good and bad to both systems but depends on the specific rider needs. If one wants lights to see the road on every ride then I can see the allure on a dynamo system. I only ride during the day so have small battery lights on the bike and helmet to be seen by others. For ultimate brightness you want multiple Cree bulbs powered by 18650 battery packs but they are heavy and would blind anything caught in their path. Candlepowerforums is a great place to learn about all types of lighting.