Re brakes...a number of us local to the area used to track the M5 at VIR in the early days. Redshift and I both experienced major brake issues leading to getting the Stoptech front BBK (which will blow you away at VIR when you experience it the first time). If you're in the instructor and/or advanced solo groups, running R-comps, and driving the car near its limits, even using the best race pads with open brake ducts, isn't going to cut it at VIR. The brake duty cycle there is VERY high as the 145mph to 40 at the end of the back straight is followed not too much longer by the 130+ to 35mph at the end of the front straight. Doing this on sticky R-comp tires while maximizing your entry speed (driving this thing like a race car), creates a humongous heat load input that the stock brakes simply can't cope with (not surprising, many street cars are similar).
I used Hawk HT-10 race pads with open brake ducts and melted not only the dust covers but also the piston seals on one side. If you drive 8/10ths or so (still seriously hauling), you can make it ok with the stock brakes.
Once changing to the Stoptech BBK and using PFC01 pads with Ti plates, all brake issues disappeared. The phenomenal stopping power is there lap after lap, 10/10ths braking if you want, no problem, not even a dust cover showing distress signs. Brake feel is of course nicely increased also with good release feel on trail braking.
Needless to say, I long ago quit taking the M5 to track events -- too heavy, and my car is too much of a garage queen now at 58k miles to consider any more paint abuse at the track...only autocrossing fun for now. I did have an open seat in Redshift's euro E36 M3 track car for track events until he went and sold it. Now THAT was a fun car at VIR. Really fun.
Chuck