I have had enough of this stupid debate. So I am taking upon myself to end here right now.
SHOT PLACEMENT! SHOT PLACEMENT! SHOT PLACEMENT!
And some bad guys are more resilient than others, so put multiple on them!
With all the new loads in +P +P+ and, coming soon, +P cubed, I believe any of the these loads will do what it takes to stop a threat in any of the three or four or five popular calibers. So instead of using brain cells to understand and debate with yourself on ballistics, and staying up all light wondering if your 9mm will do the job, fill that grey matter space with training and SHOT PLACEMENT. And the focusing on the front sight won’t hurt either.
Rant off!