The thing that has made the most sense to me is to use the most gun that you can comfortably shoot well, then practice with and carry that. The on target 380 is better than the off target 45. But, if you can shoot a round that has better specifications, then why limit yourself? From what I have observed... you don't seem to get a lot of recoil reduction going from a 9 to a 380. If you did, then it would seem like a good choice for people that do not handle recoil well. But if the kick is the same and the impact is less... not sure what you are getting aside from a smaller gun. Even if that is what you are looking for though... It doesn't seem like 380s are significantly smaller than the subcompact 9s anymore.