On my '93 3.8 the brakes were upgraded to Alpina disks, calipers and pads (reworked 750i pads). The braking is absolutely fenomenal. Never any fading, and I have never had the ABS come in yet. Since the upgrade was done by the previous owner, I don't know how well the standard Nürnburgring brakes do the job, but this is highly recommended to anyone who likes to take their M5 to the limit. Parts are a bit pricey, though. The set retails for around $4000,- (front only) in Holland.