We got <10K mile out of the stock Potenzas with my wife doing daily highway driving. I switched to Nitto Invo rears in Jan 2012 and the car became my DD in July 2012. I just replaced all four wheels with new Nitto Invo tires in Dec after getting 20K on them. And I can guarantee you I was harder on those tires in 6 months than we were on the Potenzas over their entire life. I definitely let the tires loose on corners every so often, but usually I wait for a bit of rain - I can have
a lot more fun for the same amount of wear on the tires
