Just wondering if anybody has tried the Nankang AS-1 performance 245/35/21? I have gone through two sets of Contis that only last 8000 miles on the rear of my P85. The fronts are lasting double without rotating. Only threads I could find seemed to be about 19s but the threads were in Dutch I believe. I was looking for feedback on the 21" size. I have read a bunch of mostly good reviews for that brand for other cars and was thinking about it since they wear out so fast anyway. Feedback good or bad????? Please no discounting credibility because they don't have commercials playing every 15 minutes.