Bad is in the eye of the beholder, and consider the price Farhorizon paid for my advice. For that matter, it's worth twice what he paid for it.

I've used battery powered bike lights. Lots of them are very good. This generic one from amazon is not what I consider a bike light, with its power cord and flimsy mount. I've tried high power flashlights. I came back to bike lights, because they're built for the purpose.