I ran 225/50R16s on my SRT4 ACR. With stock shocks, these tires were a little mushy, the turn in wasnt precise and was a bit slow. After installing some nicely tuned Konis, the car behaved much better with these tires (turn in was sharper and faster). The first set of tires lasted 150 autocross runs, though only 12 were on concrete. The second set lasted about 80 runs, but included about twice as many concrete runs, which is when most of the wear occured. On the first set of tires, I was first in PAX at a local event in Ohio on the day that I finally killed them off, so even if they do loose a little bit of performance with age, they were still good enough after 150 runs to win PAX at an event.