.40 S & W??!! For wimps!
A real he-man's (or she-woman's, in today's society) round is the classic .45 ACP. 230 grains of jacketed hollowpoints, such as Federal Hydra-Shoks do just fine.
If you lived a protected life from such "exposure" where ya panic over a paper cut then you'll drop from a .22 rimfire round. I have been places where victims had never seen a TV show or Movie and didn't know they were supposed to fall down and die when shot.
The best chance one has in a handgun fight IMO is to make the fastest and quickest hits on his / her agressor with a modern hollowpoint projectile that has the speed and velocity to expell it's energy inside of a body cavity vs entry and exit hole and do such with as large a diameter "permanent wound channel" as possible be it a 40 short and wimpy or a nothing but 45 ACP !
Just my opinion.....Stay Safe !