S6 setup does not have Race option. and they come in Avant only, so if you'll install them rear will sit higher.
Street setup for RS6 drives nicely but I dont like the rear look, it sits too high. By the way I have them for sale, if someone interested. I had to cut the rear springs one coil for the look. So only front springs are ok.

Quote Originally Posted by uncfrk View Post
Did you consider the springs specified for the S6 instead of the A6? They lower the front & rear more evenly.