As I said on the phone, you have fat legs... haha. J/K.
Hey I wonder if heat is a factor, since the heat generated is higher than what I have seen. Remember what it was? I think it is about 300+ rotor and 180 or so pads, at the side of pit lane after a lap of cool down lap???
we cannot blame OEM for track abuse. They should be able to withstand heat. EVO brembo and even my RX-8 OEM caliper does it ok on the track, lap after lap.
Hopefully that is isolated. I will give it another go WAY. If it happens again then some aftermarket 6 pot. Or talk to Brembo regarding some better piston...