I almost exclusivley belt carry and the largest light I'm comfortable with is an A2.... Carrying lights to destinations such as camping/hunting/fishing will include larger lights like an older 9N with T-1 turbo head, or maybe an 8AX. Todays smaller and brighter lights/bulbs/emitters really make it difficult for me to keep hauling out the old timers. I can get more lumens and similar or even better runtime with say a Vital Gear FB3 or 9P with a LF HO or EO bulb and 17500's rechargeables in a very much smaller package. Heck, swap out the incan bulbs in the same lights I just mentioned with LED's like a Q5 and that pretty much covers all the bases.
In the winter time, I can carry the Vital Gear setup in a coat pocket, with pocket clip very comfortably.
Bob