I have gone to smaller, flater pistols like my Kahr CW9 or my very slightly larger Walther PPS 9mm for carry purposes---makes a huge difference.
OK, bear in mind that people will risk their lives to save strangers. I think it's almost an instinct, species survival thing. Lots of stories, movies, Saving Private Ryan's.
Thus I always cringe when people -say- they are 'willing to use it (HG)' willing to apply deadly force. Actually, I don't think you get to choose. When pulled into a 'gravest extreme' situation, your instincts act. YOU do not. And, thus your instinct might be to freeze or flee. You might find a smoking gun in your hand and not really know what happened. No joke.
So I say "I am prepared..." and leave it at that. There is no willing to kill. I have no will to kill and will do everything in my power to not, not ever have to kill anyone. I don't contemplate it, I don't want it and I believe I have the training and preparedness and partnering up to never come close.
I just went shooting w/ my girlfriend at the indoor range in Richmond today using my H&K USP .40 and a rental full-auto H&K MP-5 10mm submachine gun. She only tried the machine gun and she almost shot the celing with it. After that, she wanted no part of it as she is not comfortable with guns, although she respects my decision to have one. But she did have a good time being in awe of my performance.