I have to say that for a bit I thought that I was getting vibration from the wheels, but later realized it was just bad pavement. As for differences I can't say as I've noticed any huge handling improvements, haven't really pushed the car too much since my tires are shot and I don't want to put the new ones on before winter when I switch to my winter tires. The only negative thing I noticed is that it tends to fall into the ruts created by trucks on the road more easily. Kinda like when youre driving over streetcar tracks and the wheels want to follow the tracks. Main thing I noticed with mine is that they rear ones rub even with the fender screw taken out... I guess that's what you get for wanting to go wider. I have 15mm in the rear BTW.