just took a test drive on the tsx. however, i noticed that before getting into the car, i saw some type of rustic build up on the surface of the disc brakes...but after the drive, the rust goes away but on the outer rim of the disc, the rust remains. i'm assuming that the calipers are responsible. is this normal for any car with disc brakes similar to the tsx? of course, the rust appears on a rainy day. thanks.