While I have never been a huge fan of the LFP chemistry, I have to admit that the really flat discharge curve even at high currents is advantageous for hotwire setups.Tough call on selecting a bulb that would match a 3S string of the K2 Energy LFP26650EV cells. Looking at LuxLuthor's charts, it seems that an ROP 3853H bulb might work well, although you might need to worry aboutwithout a soft start. Looks like it could be borderline. If it does not instaflash, it would be a wonderful option for a 3D body.Let me know what you try. I am currently using Eneloops in a 9AA->3D holder for my Mag85. It would be nice to compare that configuration to a 3S string of K2 LFP26650 cells with a 3853H bulb. It would certainly save money on the battery holder and on bi-pin adapter.Cheers,BG