I am getting new Sparco Assetto Gara 18x8 wheels today, which are supposed to be just over 21 lbs. I got them with TOTO R1R tires in 245/40-18 size, so just the next size wider, but still rated for 8" wide wheels and withing the size range for the ST (& still 25 lbs like stock). The Tire Rack mounted and shipped them to me in one day with the TPMS installed (I also got the Ford tool to link them to my car)! The stock tires are a little bit of a weak link in my opinion, at least on the track. We'll see how these do. I'll post some pictures sometime this weekend.