I only used the BB750 for fitment and to test the light, I have only ran it a few seconds at a time. I really only wanted to drive the LED at 300ma but I already had BB750 for another prodject (Micra LuxIII / BB750 / PR head Mod). I have decided to keep the BB750 in this light and have changed the emitter to a luxIII, but I had to step up to a "j" Vf bin since I couldn't find a "H" with WO tint in a T bin. I really want a Lux III with a U bin in a low Vf but can't find one of those either. Best I could find is a UX1K.