the 'normal' Wilwood/RPI kit has 11" rotors with the 4pot caliper. my stock speedlines D.E.'s fit perfect. it's as close as one could get though. it's sounds funny to downsize in rotor size, but the big advantage to the 11.3's wasn't rotor size but pad sweep. that's where it had a 33% advantage to the O.E.M. 11.0's. but i went from the 11.3 with steel lines and Red box pads to the wilwood 11.0 with Hawk pads and have to say it's totally incredible. they do have a brand new 13.0" kit with the same caliper and an aluminum hatted rotor that still weighs 15lbs less than stock. might have to upgrade to that when my current rotors are toast. don't know if i want to rid myself of my 15's though. it's nice to be able to use both.
Pros: totally incredible
Cons: downsize in rotor size