I live in Miami,FL and I have to tell you, I've seen it all when it comes to rims. 20 inch rims on an S class fit with no modifications, as long as you're not trying to fit really wide rims (10 inch or wider), as a matter of fact, you can fit 22 inch rims with no modifications. I've seen it plenty times, and no rubbing!!. 19 and 21 inch rims are kind of hard on the pockets because the tires are hard to come by.
19 inch and 20 inch will fit. But remember, the bigger you go, the harsher the ride.
1987 mercedes 300E
1995 e320 conversion(hated the 300e grill)
Monochromatic Paint (Custom Blue)
Flat Badged (front)
custom "carbon fiber" console
18 inch HP EVO rims
Sold! Now I drive a Monte Carlo SS