Originally Posted by Tomac
All handguns are relatively poor "stoppers" regardless of caliber or bullet used. Shot placement and sufficient penetration are paramount, all else is secondary.
Bottom line: choose whichever caliber you shoot the best but I prefer the 9 for greater capacity & less recoil for faster followup shots.
In the OP situation I would use a gun based on if it kicks on one end it kicks just as hard on the other. Get my point?