Interesting. The rt615s or toyo R1Rs are the weapon of choice for the auto-x guys I race with.
http://www.pro-touring.com/showthread.php?96134-BFGoodrich-g-Force-Rival-tire-launch-review-and-podcastLooks like a crappy selection of 17" sizes - if they had a 275/40-17 I'd order a set as soon as they hit the shelves.
I had considered getting a set of Rivals, but then I changed my mind when I priced them out. They were nearly double what I paid for my Potenza RE760s. lol