Believing that most of us are not retired or present LEO, or trained much in the latest self-defense tactics, and as much as we might love to, maybe not having the $$$ to attend the various "academies"; or, age having taken its toll, we are not as physically capable as we were; I'd say use what you can shoot the best, whether is be .22 LR, (Poodle shooter?).38 Special wadcutter, or .44 magnum "Do you feel lucky, punk?"

To paraphrase Foghorn Leghorn;
"PRACTICE with that round, I say Practice, boy!"

Don't dick around "trying" different stuff each week, and visualize yourself realistically in a likely scenario...NOT you standing there, yelling; "Take that, you cowardly criminal persons!",pumping 11 center-mass rounds from your J frame; (but, we can all dream, right?) but what you may do with extremely wet jockey shorts, possibly wounded, and/or with hysterical companion(s) and bystanders to deal with. Where's the exit? FEETS, save the body!