The number 1 reason is "driveability" - the newly designed pressure plate allows for more room to machine holes in the pressure plate. This extra room and holes allow OS to install clips inside the plate.

Some benefits to the clips in the Pressure Plate are:
-Smoother engagement (standard TR & STR engagement is harsher than stock (some customers like this b/c of more aggressive engagement (on/off release of power), but some don't)
-Holds floater plate down, so when the clutch is disengaged, no annoying chattering when parallel parking or sitting at stop light
-Ability to pick pedal feel, hard or soft



The best reason to use this clutch set up is to maintain that OEM like engagement and pedal feel, even with 700HP!!



BTW this clutch is going to be installed into a daily driven NYC Twin Turbo 370Z...

 

I have been looking at this exact model for my 370. I'm already a little annoyed at how noisy this drive train is and want to know how much more noise this clutch and flywheel will make?