While testing the new F56S with the 17" runflats, the ride wasn't any worse than my '12 R56S with 16" Michelen A/3 non-runflats. Also, the handling with the standard suspension felt really responsive while still being compliant.
After two R56S', I am really excited about my '15 F56S auto.

 

Go to a lighter wheel, say 12-15lbs. and non-runflats and you will have an unbelieveable difference. Get rid of all that un-sprung weight and the car behaves like a new animal...UNREAL.....