I have the Cobra R brakes M-2300-X, but havent installed them yet. Earlier in the week, I test fit the driver side (while I was installing my Bilsteins) to see how it would fit with my stock 03 rims (use them during the winter). It fit, but not by much. Yes, the 03 cobra rims will fit w/ 17's, but the Cobra R calipers are a bit larger. I wont put my brakes on until this spring when I can go back to my FR500s.
Honestly, if I didnt get a hell of a deal on the Cobra R brakes, I would have gone with the 03 Cobra set up. You can pick them up from most anywhere, especially Ebay for about half what you would pay for the Cobra R.
My 2 cents, buy the rims for $200, and if you want to upgrade the brakes, go with something like the 03 Cobras, they will fit 17's and wont cost you near what the Cobra R's do. Hell why pay TWICE the price for maybe 2 or 3 feet from 60 mph.