18's looking goofy on OUR year? Thats the biggest load of BS i have ever heard. Its simple, if you dont mind the minor extra cost in tires....then get the 18's. Either way, chances are you arent going to have great traction with a 17 or 18. Are you going for looks? Performance? You can always swap out to old v6 wheels or your stock wheels f and or the track.
With 17's there is still fender well gap unless you slam the car. 18's fill it up very nicely and dont look goofy. Show me one car that looks goofy with 18's from our year. I can almost guarantee you that if you take 2 of the same wheels in 17 and 18 that the 18 will come out looking better. Go ahead and try it....take a 18" saleen wheel and the same thing in a 17" replica...wont be close.
Thats not to say 17's dont look good. I had them first on my v6 and i too thought it looked great. But once you go 18's you wont ever go back unless you are going for drag wheels or something.
Its up to you and whats most important. Cost? Performance? Looks? 18's are worth it. Thats the bottom line.