Do you use HP as range ammo? The thing is, you're not going to be able to choose the background, place and time of a SD situation. There is also not much hype when it comes to good defense ammo and there are plenty of professional and end user tests to proves so. There are lists of top grade defense ammo that are good for SD and I know Gold Dot, Ranger Ts and HSTs are among the top 5.

I've seen the performance differences with the low grade generic HP ammo and premium in the same 4 layers of denim/gel tests which also included some FMJ. Certain calibers due to their speed are less likely to over penetrate and some calibers are favored in FMJ due to lack of penetration. I'd link a ammo list over at ARFCOM but that is forbidden here.