Okay, so I'm a total chick here. I just purchased a 2011 IS250 and I HATE the alloy rims. Hate. I have a 2007 IS250 still and LOVE my 18" alloy rims. Is there any switching around I can do? Or am I beat because of the difference in tire size on the 2007 vs 2011 (wider in back, I'm sure you know.)?
In respond to 90mx83, even though the 18s are little bit heavier than the 17s, it will not affect performance much and it will not be even noticeable in daily driving. There might be tiny loss in term of handling and acceleration if the car get pushed to the limit but again it will be very very little difference.