I had to replace our rear pads around 50,000 miles. Quite a bit of city driving takes place, and it's only been over the past year 25,000 miles that most of the wife's trip to work takes places around 50mph, versus bumper to bumper traffic. We didn't machine the rotors, and I just replaced the pads. The rotors looked fine, but then again, I guess you can't tell if there is any warping by looking at them. There's still some squeaking here and there, and the front pads probably have less than 10,000 miles left on them. The guys at the local tire shop told us we're lucky to get 30,000 miles out of brake pads here in the DC area. We are currently at 53,000 miles.