better hope they hit the vitals on first shot then, unfortunately thats not always the case. Id go with a double tap well placed to the chest with a 9 over a .45 that may or may not miss vitals and the second shot hitting arm leg etc, or even missing. idk thats just me though everyone has there opinions. I know forsure i would be much more confident in well placing a double or trip with a 9mm then getting a 2nd or third accurate off with the .45 like i said though just my opinion we all have preferences lol.