I wonder if this is a design flaw, as BOTH mine and my wife's succumbed in the same fashion in the last year or so. I didn't know they could/would repair them- I'll have to see if I still have them. Other than that, I agree on the brightness, especially with respect to price; my old 350 was as bright as I ever felt I needed (great flashlights when not in use on the bike, too!)
Currently we're using another Niterider (550/ hers) and a Light & Motion Urban 900 (mine). I'm not sure the NR isn't every bit as bright as the L&M, though I suspect the beam pattern has a lot to do with that.