Dear Dr Sard, I have also run the Bridgestones as a favor to a friend. They seem identical to the Michelin Sport tec M-1's. Both tires I work great. 4500 - 5000 miles I was running on cords but the potential for a easy tire to warm up which works for the track and street is very high with both of these tires. Summer is coming so the Super Cosa's will be coming out. Catch ya later.