Rears are not as large and wont' weigh as much, but the front rotors were 23.5 lbs stock and 320mm, the Stoptechs are 18.1 lbs and 355mm, have more mass and better cooling. You drop over 5 lbs a corner of rotational AND unsprung mass right there. You could swap out the rear rotors with stock sized Stoptechs (slotted too) and likely kill another 3 lbs a corner there, as they are smaller rotors.
They have red only in stock, but if you don't mind paying full price (their closeout deal is crazy as hell cheap) you can get them in black for sure and I think gray -
http://forums.quattroworld.com/s4b8/msgs/20966.phtml
I bedded mine in on the way home, by the time I had them up to temp I was rolling slowly in neutral on a gentle slope and a guy yells "Hey dude your brakes are smoking!" I waved and said "Thanks I know!" and he seemed confused. I didn't come to a stop with the brakes applied so it was all good, drove around at 40mph for about 5-8 min with no brake use and got them back down to temp, they smell good now and have not squealed once.
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