I really do not understand all this debate as it constantly boils down to performance vs. durability.  I never knew all the kinds of oils in my 997S which I tracked quite a lot, but then again I neither had problems nor did other ever flag them.  Having said that I did overcook my brakes (twice) but that was when I first started tracking and did not know about cooling down Smiley 10

Bottom line from what I have read both here and in general, the GTR should not really be tracked in anger, whether component stress, or warranty issues, the costs of doing so are just not commensurate with the sticker price of the car. 

Horses for courses, much like the BMW M brakes which are not supposed to last on track (never tracked my M at the time so heresay from my part).  Enjoy the GTR power, or enjoy the TT/GT challenge is my take.