It definitely rides firmer than my '01 330xi - run-flats and 18" sport package wheels are much "sportier". I do like the wheels; they're not as "common" as some of the others.
It's currently parked in the garage next to my son's Monaco Blue/Black leather 335i Coupe. He likes my lighter colors better - but then he bought used and had to take what he could find to get the manual tranny.
Funny thing; even though it's essentially the same block, and both are turbo-charged, things are on different sides of the engine compartment!