Z4 2.8i 17" vs 18" wheel ride quality

I had a 2009 Z4 3.5i with 18" wheels (no sport package) and turned in the lease about a year ago. I miss the car and have looked at a few others like Corvette, Boxster, etc but keep coming back to the Z4. I plan on getting another in the fall when my 5-series lease is up as I have another daily driver.

One thing I did not like about the 3.5i and 18"wheels was the ride as impact harshness could be pretty rough with the low profile runflats. The car also felt heavy at times. I recently test drive a 2.8i with the 17" wheels and loved it. The car felt very light on its feet and the ride was better. I do not care for the look of the 17s though, and ultimate stick in the corners was definitely compromised by the smaller contact patch.

Has anyone compared the 17" to 18" wheels on the 2.8i? Does the car still feel light on its feet, and how is the ride and impact harshness? I am thinking about getting one of the Sport Packages to go with the Canyon Brown Interior, mostly for the better looking wheels.

Getting rid of the runflats is probably what you should do...

I will be doing that regardless of whether I get 17s or 18s. Leaning towards 18s and BFG tires... they have a model that is about $700/set and is very highly regarded. PSS a bit more than I want to spend.

18" with regular tires (I only switched from PS2s to PSS so I don't know about the BFG's, I would recommend Continental actually) would do more of what you want than going to 17" RFT. Obviously 17" will feel softer but if you loved the 17" with RFT, chances are you will do fine with the 18" non RFT.