well ive seen the online police reports of guys hopped up on meth or crack needing multiple hits from shotgun slugs to drop
That's true. You can have failures to stop with virtually any handheld weapon.
However, I have to say that the possibility of failure shouldn't encourage people to use projectiles that are known to be inferior for self-defense when other options are available.
If LRN is all you can get, then use it. If you can get anything else, practically anything else will perform better.