Just thought I would post an update. I bought a used set of 18" style 210 with some decent rubber (of course no TPMS even though seller said they had them
). I had bought some 20mm spacers for the rear and 12mm front and was going to use them for the 20"s so thought I would throw them on now. I would highly suggest if you go this route to use spacers. The clearance in the rear is minimal and the offset looks horrible with sport package. I have attached some pictures so others can see what the rears look like with 20mm spacers. If you are planning on doing this I would probably go 25mm or more
Also, The 18s seem close to the 20s in weight but after install it definitely felt quicker and seemed as though the tranny shifted smoother. Probably just all in my head but the ride was much smoother with all the sidewall