I'm not big on shotguns & rifles but I did hear that many tactics & armed professionals put down the pistol grips & pistol grip stocks.
I could see the merit of a shotgun pistol grip style stock for last ditch or CQB type incidents.
I like the Knoxx type but the MagPul line looks practical too. It won't win any beauty contests but it will; "ride the river".
ClydeFrog