Unfortunately, just the way way things played out these wheels got the 615k+ not the newer 660, probably a good thing just to get a feel for how different tires feel.coolhandluke wrote:I'm a big fan of K1's. I haven't personally tried the new RT660's but so far I've read positive feedback from peers in our Tire Tech thread for track use. For street driving, a 200tw tire in the Extreme Performance is pretty much the same all around IMO, wet performance would be the main difference in tread design.
I’m just glad to not be 100% dependent on one set of wheels now and have to worry about damage or hunting something down that will fit.