I am 230 lbs and can admit that my little glock 27 in 40 recoils enough that I can not shoot it as quickly and controllably as my full sized steel 1911 in .45. I do a lot of tac drills with the local police guys, (I am not law enforcment, just a gun nut and range guy who gets to pratice with them) and when we go through 1000 rounds in a couple of mornings it sure would be nice to have a glock 17 or 34 to keep constant control under speedier drills while saving money on ammo.
Now, that being said, my carry gun is still usually the .40 model g27, or if i'm dressed right for it, a .45, because honestly if and when I have to use lethal force, I don't want to be worrying about "well placed" shots and "follow up shots" I want to know that if I hit them, ANYWHERE, that hit will cause enough instantaneous shock, fear, and movement that I am safe and the assailant isn't incapacitated. 9mm was a good deal for the geneva convention guys, and the whole, "carry more ammo per truck pallet" and "take the medic off the field with the injured" military crowds, but you notice that 80% of law enforcement which are don't care about shippnig large amounts of ammo, and don't carry about geneva conventions, are 80% all carrying 40 caliber in hollow points.