I just recieved and installed my FFP dogbone today. There was a HUGE amount of difference over the stock one. With the sock bone in 151,xxx miles appearing to be in ok shape. Switching from Reverse to Drive would let the engine roll around 2-3 inches. After installation the engine would only roll less then .5inches at the most. Pluses!!!!: more agreesive sounding engine, SMOTHER shifting in the transmission also seems to have solved my tranny slip problem. Shifting Time has droped significantly. Also the FFP ingravment looks kinda cool, i might paint in the lettering. All around it was worth every penny.