Johnny blue
Bluelight Crew
I like a 9mm cause its easy and cheap. PFF if you want stopping power I'd go .40 as its usually cheaper and more common. Cops usually carry 40s. I'm no expert and I'm sure there are plenty here that have shot more than me but I've shot a 357 and 40 and IMO there's not much difference. Personally I'd take a 9 because they are so much cheaper and easier to put lead on target.