These questions have been asked many times,and always seem to get the same answers.It is a package-not just a component.The factory did a very good job of putting out packages for different types of performance wants.The reason 8 3/4 comes up in conversation is because it is the all around great performance rear.You will hear all kind of stories about how I got this part cheap and threw it in and did all kinds of mods and it is still going strong.Key word is what did it really cost?Believe all the bench racing stories that you want,but it really comes back to what works and what makes you walk back home after a few holeshots.My money goes with the 8 3/4