buzz:
My own preferences:
OWB: Don Hume JIT (leather), Glock Sport holster (polymer).
IWB: Alessi Talon (leather) Sidearmor (kydex). Full disclosure: I don't own either of these, but I've handled them, and I want to.
AMMO: May not be the best choice on paper, but the best balance of accuracy and controllability I've found is 185gr Winchester Silvertips.
As an aside, if you want a fuller grip and something closer to an intermediate frame pistol, try the +1 magazine baseplate from Pearce. Sacrifices some concealability for shootability and 7+1.
My G36 has taken a backseat to a S&W M-60 and a Colt Pocket Nine for everywhere carry, but it's still a good balance of "comfortable/comforting" in my mind when I'm in a ".45 mood".
Best,
SA Scott