Good quality with one big flaw - Griffin Armament C2E Contour Connect End Plate

End plate is well machine and the qd works great. However, when I tried to stake it to the castle nut, the steel that it's made out of would not deform. With a mil-spec end plate, it only takes 2 or 3 hit with a punch or a hammer to properly stake it. With this, I hit it about 20 times and barely made a dent in the steel. Went to read the product description realized why, it's made out of "heat treated ordnance grade steel." That makes it very difficult to stake.
Would be great for a range toy, but not for a duty gun where the castle nut needs to be properly stake.