I got mine when it came out in 2008 and used it as my only light until spring 2010. I still use it since it is the only light that will fit on my k-wing handle bars on the cross bike. It has never let me down even an hour past it's "run time" of 3 hours. The light does get dimmer after an hour or so now and seems dim on a bike trail at 18-20 mph. However for the sub-hundred price I paid when it dies I will purchase another one.