Listen. The best tool to have for any purpose is the one that you're familiar with and willing to use for that purpose. Some guys I've gone to the gym with swear by .25 ACP, and I recently met a grandmother who packs a 10mm because she thinks .45 "Is for sissies".
You do you, queens and kings.
i go for comfort, something that's not too wide in the grip, or too narrow, easy sites to look at and comfortable to aim. Size doesn't matter if you don't miss your target.
You do you, queens and kings.