My current “favorite” is the YLP Gekko 1.0. It’s good for what it is, and I like it, but it’s a bit under battery-ed, and not quite punchy enough to be ideal for my uses. It’s inexpensive (with the initial discount code anyway <$40USD), puts out acceptably high output for up to 2 hours of running or skiing, high CRI, and lightweight. How I use it and why it comes up a bit short: I basically turn it on to max (~900 lumens) if I expect to be in the dark less than an hour. If I expect to be out for more than that, I set it to max and then ramp down a tiny bit to still have enough light to move if I’m out for 2 hours. My usage is winter (have basically midnight sun in summer), so the cold has a positive effect on LED cooling, so BLF complaints about poor construction/thermal execution behind the board hasn’t affected me, but the cold does reduce the affective battery life. To be truly comfortable, I really need a 2x18650 light or 21700 light because I’m running less brightness to have enough runtime, and while the near/medium optic provides the spread I like to not have tunnel vision, I’d like a bit more punch. Duo (or more) emitter lights with multiple optics/mule combinations are what I really need. Also, it has the typical silicone headstrap that is more for the BLF user who wants to use it in hand part of time. It’s not as comfortable as dedicated padded hard plastic holder with more surface area on the head that doesn’t have to be squishable into a pocket.
My headlamps go back to the ’90s. Princeton Tec Solo (halogen), PT Aurora, PT Quad, PT Eos (~2004? after doing a lots of mods to the Eos - emitter swap, optic-to-reflector swap, and external battery - it became my first headlamp that was truly usable for running fast), Magicshine MJ-808 (2009 my first high powered ~600 lumens budget headlamp), Gemini Lights Xera (2011, smaller than Magicshine), Gemini Lights Duo, Yinding (cheap Gemini Duo copy). I have also used my GF’s Petzl Reactik, Petzl Actik Core, and Petzl Nao. I’m probably forgetting some. Just about all the lights break, some sooner than others. My overall favorites that I have used are the Gemini Duo/Yinding (which I used on the Duo headstrap…) The Gemini’s button programming was more sophisticated, but the Yinding lasted me about 4 years vs about 2 years for the Duo. With either the Duo or Yinding, can do a wide and narrow optic combination, 2x18650 battery pack had enough capacity (went through 3 sets), and the headstrap system made it more comfortable and stable than the typical L-shape 18650 style silicone headstrap despite weighing 2x as much.
I always wear them on my head.
Allowed one, I’d pick something that I haven’t tried yet, assume no budget, and assume that I can do an emitter swap. I like the design of the LEDX Lights, and their smaller new Snok looks good. Or the similar Lucifer M6, since I haven’t had hands on either one. The LEDX looks more sophisticated in design with deeper cooling fins, and better looking headstrap. I only don’t like the 6000K emitter. Reason is that both companies were founded by an orienteers, so they understand running/skiing with light balance/stability and light distribution for those activities. On high at 2000 lumens, it doesn’t blow out the map you are reading, it’s evenly distributed on the ground in front of you, and has punch into the distance to where you are headed/looking.