I have a first-run batch of the LumaPower MRVs with Q5 LEDs. Since the beginning it has given me problems when running 18650s. The LED will flicker and drop-out, even with fully charged cells. No problems with 2xCR123 however.
I've been running it for a while now on CR123s, but the time as come to modify it in hopes of getting back to using 18650s.
I'm hoping for any suggestions on the names of CPFers who can handle upgrading the engine and LED of this flashlight. I'd like to drive an XM-L with an 18650 using this MRV as the host.