LB, it looks like we pretty well agree on this one. Nice for a cheap, bang-around headlamp. But not something I’d trust my life with.
Getting to the emitters, as LB said, is easy. Doing something with them… maybe not so much. If you want to replace the custom PCB, you might be able to fit 2x 16mm in there, but I don’t think 20mm would fit (I forgot to measure that). Easiest thing would be to reflow other XM-L2s in the original MCPCB.
As far as runtime goes, I measured 200 minutes to empty using a Samsung 35E:
