Definitely stay away from Niterider! I've been through 3(!) Trail Rat 2.0s, and none of them lasted more than 6 weeks. I'd just be riding along in the dark and phittt...the light would go out. Yes, the company was good about replacing them, but that didn't save my ride, and would have been small consolation if I had had an accident in the dark! I've also never received any feedback on what was wrong. I've also been through a couple of Performance Viewpoint Pros...it's apparently hard to find a light that holds up under daily use!

I have a Planet Bike system now that seems to be getting the job done, but I've only had it for a week or so, so the jury is still out. Good luck with your search!