watch where you charge the lights from AliExpress, theres been all sorts of reports over on Singletrackworld about the battery packs overcharging and basically blowing up... Always charge in a solid non-flammable receptacle (I use an old "ammo-can" with a couple of relief grooves for the cable inward) and DON'T leave them unsupervised.

as to recommendations - http://singletrackworld.com/forum/topic/2016-which-lights

(up until about 4 winters ago, I used to self-build MTB lights, but basically, the Cree Emitter light units from places like "magicshine" and the like pretty much just killed off building light head units... battery packs were always the more difficult thing - I used to build with a view to using 7.2v NiMh remote control plane batteries (then use a reputable source for the battery and a "proper" balanced charger for them, but that's a bit of an expensive way to go about it - but back then it was pretty much the only game in town...)

I've got a little out of touch with the state of the art at the moment - hence simply recommending reading the STW thread - those guys are out there on the MTB on a regular basis, using the up to date kit. I'm just using my old relics (which are perfectly bright enough if I'm on my own - problem comes when you ride with someone else who's got a brighter light than you... if they're behind you, you're permanently riding in your own shadow, as their mega-zillion-lumen light overpowers yours and casts a shadow of you down the trail...)



I'd definitely recommend what Clive said though - something with a pretty wide beam pattern for on the bars, and a more focussed spot on the helmet...

Check out TrailLED. Great lights with good output. http://www.trailled.com/