HansGruber
Ronin
I think pretty much anything you actually train with can be effective. The only disadvantage I see with a PCC is the " Things that go bump in the night" scenario. You will still be firing a single, small projectile, most likely without aiming. True enough your odds of hitting an attacker are pretty good, but how many bullets are you going to loose to do it?
I see your point, but...at those distances, you don’t have a patten out of a shotgun—you may as well be firing a slug for as tight as they pellets will group.
And all things being equal, a miss is a miss...and with a shotgun, it’s a pretty high percentage of your capacity.