What driver for 3 led mag mod?

[KarlH]

I have a few high cri seoul p4's and want to mod my 3D mag lite with 3 of them and have multiple levels, at least low/high and preferably low/mid/high, and no strobe/signal or any other useless to me modes. I will be using 3 D nimh batteries since I have several already and don't want to get into AA packs or lithiums of any sort for this. I have been looking and can't figure out what the best driver, or drivers would be. I'm kind of leaning towards a tri-flupic since a boost driver like a maxflex is not that efficient and generates a lot more heat given the low voltage of 3 nimh cells and the voltage needed to drive 3 led's in series. Does anyone have a good suggestion? I'm dead set on the batteries I will use so no point in suggesting anything different on that line.