Two CR123a do not work in an 18650 Zebra. Thats why I bought a Skilhunt H300 instead.

Maybe in the past lithium ion batteries were a problem with cold temperatures. You are still going to get some voltage sag. As long as you don’t need turbo it’s not too bad down to 0F or -20c . 18650 batteries with at least a 10 amp CDR seem to do fine. Years ago there were a lot rated at only 5 amps.