I consider tire-driven lighting to be more conversation piece than acceptable technology. I'd prefer something that wont get bent or damaged by a stick, or a minor mishap, and which won't wear down my tire and increase my risk of blowouts and premature replacement.

I can see using them for occasional, or emergency use, but I'd rather have a quality dyno-hub with lighting elements and patterns that do more than let me see what I'm going to inevitably crash into at the last moment. Battery-powered is also preferred, so long as it is functional and efficient.