CobraK, I honestly believe it's personal opinion. There's some pluses and minus for both. But I can tell you that I prefer the 17" wheels.
One thing no one mentioned is that it is often difficult to get the 15" wheels centered just right when reinstalling the lugs, therefore causing wheel vibrations. As far as I have seen, the knock offs have not had this problem.
Also, my 315s are just under the fenders. They seem to fit very well on the car. Finally, I race and I would much more prefer to race with 17 harder side walls. For the street, it's up to you.
By the way, love the color!
James
