Hmmmm,, well lets be honest about all this, as in adj uppers vrs stock replacement tube uppers. The biggest advantage to using adj uppers is in the ability to to change the front end geomtry to ones advantage.. As in lowering the front roll center of the car,, and many other adjustment that you can do with the chassis. But make no mistake changing the roll center is a big improvement to the car. Now some guys will know how to do this and others don't have a clue, those that do will have a distinct advantage over the rest of the class. I don't believe that was the intent of the rule change. If everyone has to use a stock replacement upper than that keeps everyone on the same page ware this rule applies. It's a good rule change and lets not get carried away with it.. JMO..