For those going from 18's to 20's, how have you compared the ride?? I am debating switching to 20's, but already have a pretty stiff ride with Eibach Sports (although I can ajust the stiffness from my Dspecs).

Also, if you have 20's, what tire sizes are you using?

 

The larger wheel shouldn't provide any stiffer of a ride than you currently have. However, because of the reduced sidewall of the tire the harshness will likely increase. You also want to pay closer attention to things like pot holes. There's less tire to protect those big wheels.

 

I went from stock 17" Bullitts on FRRP springs to 20" Shelby Razors with 255/40 all round. The ride is a little less forgiving, but not enough to notice after a day or two.

I'd never go back to the smaller rim.

HTH