They do offer a top-of-their-line cast iron 405mm front and rear diameter rotor kit for 4190 bucks, with everything included, including park brake compatibility, calipers, mounts, pads, stainless pistons, extra dust boots. That seems pretty good, especially with the cross-drilled-only rotors, since I do not like slots. Curious if Porsche has the tungsten-faced rotors locked up with patents, because that seems, by far, to be the way to go.
That seems rather hard to beat. I am not inclined to replace the well-proven Brembos, however.