While I own a .45, besides some other calibers, I prefer my 9mm Glocks and my Browning HP in 9mm. I can double/triple tap faster, and with the right HP ammo, I'm sure that if, God forbid, I had to shoot someone in defense of my family, not only would I hit them, but I would also inflict great bodily harm on them....ballistics tables be damned.
The important thing is to carry what you can shoot the best......and not get too hung up on caliber.
Having said all that......in case of a breakin to my home, or a Zombie attack, my Ruger .223 carbine would be my goto weapon. 20 rounds of hellfire as fast as I can pull the trigger.