Do you think the clutches would have been good if you didn't have the wrong fluid in the tranny and did you notice any improvements in shift quality since you are perfect data source as you went from pd unit to fresh zf unit instead of worn to fresh pd unit like all others.
I actually forgot about the fluid problem until you reminded me. The shop the previous owner took it to put in LOW VISCOSITY ATF-1 instead of the regular ATF1. I didn't notice until I compared fluid color after removal, and my transmission guy said the clutches burned up because of "lack of fluid pressure".
My car has the stock transmission cooler/radiator that helps a little bit. I'm unsure of the longevity of the clutches but Jason was confident that they are more reliable than OEM clutches, I believe him. Without a trans cooler but with proper fluid they should last a while, IIRC the material of the clutches heats them up faster which is why the cooler is needed.
I bought the car with the PD clutches already installed, freshly rebuilt and it lasted like that for 1000 miles. There was NO tune on the transmission and it never slipped on WOT. With a tune I'm sure the shifts could have been faster and harsher, it wasn't what I was going for at the time. Now I have xHP stage 3 on the OEM clutches, shift time is very quick but it slips sometimes on WOT.
I was driving on the already-burned clutches until I lost my 4th gear on the highway, I had NO idea anything was wrong with my transmission. The clutches are really top notch.
In comparison, shift speed doesn't change, the shifting is a lot smoother and you can really tell the PD clutches can take what you can throw at them compared to OEM. All in all, I would suggest the upgrade if your current transmission is dead and you want the upgrade or you can't afford to swap a DCT in. The ZF6HP21 is really a POS compared to other units on the market, we should have gotten the ZF6HP26 from the X series imo.