As alluded to by most, I carry a variety of different guns depending on the circumstances. And while I feel pretty confident in my abilities with respect to each, I have experienced the momentary confusion with regard to controls that can occur in a sudden emergency. We all think we're real smart and well trained, but I'd venture to say that when there's about a gallon of adrenalin coursing through your system it could be a different story.
So.....anymore I almost invariably carry either a cocked and locked 1911, or a revolver or semi-auto with a double-action first shot. In the case of the semi, I never use the safety, keep one in the chamber and rely on the DA feature.