I saw this thread and figured I would ask the same question. Only difference is the roads in Boston, Taxachusettes are really jacked up ( Mostly in the city due to the construction) I'm really considering 17's for my 6thGen because of this but love the look of 18's. I'm only lowered about 1.5 front and back on Koni Yellows and Eibach Pro Kit springs. The ride is already pretty firm. How much of the acceleration is affected by the 18's?? Anyone?