There is no reason in the world that would make that PGO grip better than a full stock.
Harder to handle, harder to manipulate the safety and action release tabs, harder to maintain control in a hand to hand encounter, harder to fire accurately and far less options for carry positioning or firing positions.
NO PGO equipped gun is going to be as serviceable to the owner than a stock equipped gun. And no PGO grip is going to be comfortable to fire repeatedly to gain the skills to make you or her even remotely adequate in the range of possible situations you may bring your shotgun to bear.
All of the recoil will always be transmitted to the hands, wrists and elbows of the shooter rather than the shoulder that than transmits it completely thru the body where it is mitigated thru wide spread absorption of shock wave...
That was the long way of saying "Yer better off with a traditional stock than any PGO or PGStock..."
Brent