There is an interesting discussion on Remington 870 Forum. jdinny posted pics of his Remington 870 with ATI AR-15 Scorpion Recoil Pistol grip on Mesa Tactical LEO Stock:
Gives A Tactical Shotgun M4 Carbine Handling; Optional Recoil Reduction System.
On SALE on Brownells: http://tinyurl.com/ogv8dek
M1AG30 has posted nice pictures of his Remington 870 with LEO Adaptor and Magpul Stock on Remington 870 forum: