I propose the main benefit is to reduce over penetration and that the slightly bigger hole and cutting increases the chance of death without reducing the aggression of the attacker.
In other words I dont think expanding bullets in pistol calibers are likely to stop aggression any quicker in the short term than a non-expanding one.
That being said jhp's are best for 9mm and similar power levels as long as they arent big-expanders that cut penetration heavily.
Bookmarks