It's kinda' like the........."do this, don't do that......stand this way, not like that..........hold it this way, not that way.............." I agree it is best practice to choose your carry weapon carefully and then practice with it often using the ammo you carry. But...........that doesn't mean one shouldn't try different guns, calibers, etc. Just be sure you are proficient with what you carry. Although I started out liking 9mm, I only own one now. I now carry the .45 about 98% of the time and own several other .45's. I also own or have owned several other calibers (probably like the majority of the people here do) in .22 LR, .22 Mag, .44 mag., .44 Special, 10 mm, .40 S&W, .32 S&W, .357 Mag, .38 Special, .380, .45 Colt, etc. Variety will spice up your life.