Just noticed this thread, hope it's not too late.... For starters, I wouldn't call the M3LT a massive light; the head is the only large-ish thing about it. I use a simple
M@glite holder, the ones they make for their D and C units, ie, the ring mounted on a strap. This works fine for my present purposes but I'd hate to do a lot of running and jumping with it- the light would likely be gone. The best thing would be to try various holsters out after getting your light; if you have any suitable stores in your area at all,you should be able to find a slip-through holster that will suit the positon you want to carry it in. It would definitely have to be a bottomless holster though, if you choose one made for a more usual CR123 light.