I use the F.B.I. technique almost exclusively (side from the VERY ocassional Harries in close quarters). IMHO, most fire that you would draw from a suspect would be directly AT your flashlight because this will be one of, if not the, only reference that the bad guy will have to shoot at you in the dark. The F.B.I. technique is good because it gives the bad guy the perception that the shooter is much "further away" than where he actually is, essentially drawing fire away from your center mass. But, like anything (choosing the right sidearm, flashlight, etc.) it's a personal "comfort" choice more than anything.
Also, another consideration is steady on or intermittent use. Steady on is great for being able to consistently have a sight picture, see where you are going, etc. but it can really project your location prematurely. Used intermittently, the light can also be very hard to "keep track of" from a bad guy's standpoint. Don't forget that the light can also be used to blind the other party, and can be used as an impact/pressure weapon as well if needed. A light (or backup light, really) can also be used to throw or roll into a room to gain a leg up with lighting the scene from behind cover. This coupled with the "shock effect" (Bad guy saying "What the heck was that??" and peeking out or making noise thus giving away his location)All these things should be considered when choosing which light you want.