Larry,

Check out this article:
http://www.stoptech.com/whitepapers/warped_rotors_myth.htm
Maybe it isn't rotors but rather pads with insufficient temp capacity?

I thought I'd ruined a set of rotors recently, upon tracking my 500 at The Glen running only Euro-spec front MBZ pads. Left a LOT of pad material on the rotors, and the sensation of warped rotors upon braking was shockingly severe. I swapped over to a set of Axxis Ultimate pads, and in about 500mi. of street driving my brakes are (finally) back to normal. Never would have believed it!

__________________
"If God had meant for us to walk, why did he give us feet that fit car pedals?" Sir Sterling Moss

Michael
2014 E63S Estate
2006 SLK55
1995 E500
1986 Porsche 944 turbo