I bought my Night Rover XTRA NiMH in October. Have used it on average 4 days a week for commuting. A typical duty cycle for me now in December is 1.5 hrs of mixed low-beam and both-beam opeation, then charge for 12.5 hours. I'm happy with the light so far, trouble-free. Coldest temp I've used it at is 28 degrees, yeah, I know, that's not cold by Buffalo standards but didn't notice any performance drop off at that temp. The light switches do have a 'cheap' feel to them but they work fine and are easy to operate with a glove. The beams have plenty of side spill to illuminate stuff on the side of the road as well as straight ahead. On a dark paved bike trail with both beams I have full confidence to ride 20mph.