I'm using 16 inch STI goldies and 225/50ZR16 Continental ExtremeContact Sport, it's great. This tire size would put you at +0.04% versus the original 215/40R18, so effectively, as "exactly the same size" as it's possible to be.
I bought the wheel set for about 450$ canadian and I sold the 4 michelins that were on them (not the right size) for 80$. Since they were old wheels, I had two of them with *slight* bends to the inside lip, the worst one had a runout of just under 2mm, so I had to have that taken care of. Sandblasted, fixed curb rash with Loctite 97453 aluminum epoxy and repainted. so all in all, a "cheaper" wheel set, but you gotta put in the work to run "vintage" wheels
