I know that it is too late to change now but I was looking for a good priced wheel and I got 17". I have had some comments that 18's would have looked perfect. I didn't want to sacrifice too much ride comfort with my Benz though. Are 18's better in performance than 17's? thanks for your imput.

 

The fastest way to dramatically improve a car's appearance is with larger wheels. My CL is SL both came with the 18" wheels and the ride is darn good. I would have stepped up to at least an 18" wheel and had no regrets. Sometimes it's better to wait and get what you want.

Fortunately for you, you only bought wheels. Last year I bought an SL500 and drove it three months, before I got rid of it and bought an SL600.

 

I would have thought adding unsprung weight to the suspension would make the handling worse?
Stick with 17s.

 

When I ordered my AMG's for a 95 E320 coupe, tire rack advised me not to go with 18's due to rubbing issues. So I went with 17's, but I soon got H&R springs which dramatically lowered the car 2" and completed the look. It just looks like it needs something when wheels are upgraded with lower profile, and then you have a huge gap between the tire and the fenders!

 

Good I am happy I did the right thing. I have the H&R springs waiting install but was wondering do I have to have new shocks after I get the springs?