Last winter as I was commuting on MTB trails in the dark, and really unhappy with my 6yo Cygolite handlebar light seldom shining where it was needed, I asked on MTBR for recommendations. I also wondered how much longer I could expect it to last.
Their tastes tended to the fancy, like wireless handlebar remote for the helmet light. But generally they advised a spotlight on the helmet and flood light on the bars, preferably in matching color (bluish or yellowish). The guy who posts the most had some favorite lights, the one he liked best for the handlebars (
Revtronic BT40S) was sold batteries-not-included, or charger, since it takes a pack of higher voltage than USB. It also has no beam cutoff, it's going to give anyone approaching some glare. I also learned that my model of Cygolite has a perfectly standard lithium cell that can be replaced for peanuts if it dies... can't say that for the Hotshot tail light, though.
At the time I bought my Cygolite the Chinese lights had not yet taken over Amazon. They get massive positive feedback because they solicit it; if you look at the 5 star reviews they say things like, "It worked when I took it out of the box, 5 stars!" And if you look at the 1-2 star reviews you see some tales of woe. Average user is surely somewhere in between.
After that was my heart surgery and I stopped thinking about bike lights until just now. Time to shop...
Here's a review thread from that forum
https://forums.mtbr.com/lights-night...z-1105995.html