I do a lot of night rides and early morning rides so this light gets used 6 days a week right now. I have used Niterider headlights since 1998. This light makes a buzzing noise and I have to play with the switch sometimes to get it charge.
Light works well. Easy to charge. Not crazy bright, but plenty bright to night MTB with. The mount doesn't get big enough for large bars at the stem.
I have another older model, this newer clamping system is easier to use and faster, even with gloves on. Used for a number of 1-2 hours rides, no issues at all