It doesnt matter, if when that day comes you only end up shooting him in the leg once out of 10-15 bullets because you never went to the range and practiced. I would take 10 guys into battle who all owned high points, if they could consecutively hit a 8" pie plate at 25yds on the move.
Unlike most other people out there who think they know shit about handguns and make stupid comments like, get a .40 for personal protection.
Go to a range and rent 5-6 guns. Shoot 100 rounds out of each gun. See if the range place has a holster you can throw them in and walk around, sit in a chair, sit in your car, run around the building and see which one fits you the best. Why buy a Glock 23 if you cannot even fit your man hands on it? Why buy a 1911 if for the life of you, yo ucannot hit the broad side of a barn.
Dont fall into the hype of buying guns off of internet research. I feel i am a pretty damn good shot and there are some guns out there that I cannot hit shit with consistently. Anyone can shoot small groups from a rest hitting paper under no stress conditions. The same doesnt apply when your hands are sweaty, hearts racing, there is little to no light, and the target isnt sitting still.
End rant =