OOO! I have read something about that. It was in Gun Buyer's annual presents # 34 Special Weapons for military and police magazine. It says that it is being used by special forces, it enhanced controlability on full auto, due to lowering the action in relation to the stock and suposedly fits so tight that you don't have to glass bed the reciver to the stock.
they also said that it reduced felt recoil. weather or not any of that is true I don't know, I haven't shot one. And I think someone is making a knock off because I have seen one at a gun show and the guy said it wasn't the one from fulton.