The SSR Comp C have been redesigned for the STI so they are now offered as fitting the STI under a different SSR name for that rim, according to some that have already purchased them. I think you can see it on tire rack.
Russ keep us posted of your experience at the track. Are the rotors you have any different than ION's or are they basically the same?
I think ION's offers some 48 veins. I am curious if IoN's is the same thickness if your are different.