I carry different stuff based on the perceived needs of the environment that I'm going to be in. My preferred carry gun is my 6+1 shot P245 in .45 ACP with an 8rd reload. I like the way that gun shoots and I'm very accurate with it. In certain circumstances, though, I feel the need for more capacity so it gets swapped out for a Beretta 92X Compact for 15+1 9mm. Going the opposite direction, if I'm needing something small and light and going to be in a very low-threat environment, a scandium 5 shot .38+p J-Frame is the weapon of choice.
I don't think there's any magic to any pistol caliber (internet memes about the 10mm notwithstanding )...at the end of the day it comes down to shot placement. If you hit vitals, you can get a pretty quick stop. If you don't, you're stuck hoping they have a psychological response or lose enough blood to pass out before they kill you back. I've seen both. Pick a gun you can shoot well that's appropriate for your environment and the threat that you are most likely to encounter.
I don't think there's any magic to any pistol caliber (internet memes about the 10mm notwithstanding )...at the end of the day it comes down to shot placement. If you hit vitals, you can get a pretty quick stop. If you don't, you're stuck hoping they have a psychological response or lose enough blood to pass out before they kill you back. I've seen both. Pick a gun you can shoot well that's appropriate for your environment and the threat that you are most likely to encounter.