GS F is a very good car. My wife likes it a lot. Stable and comfortable. No any body roll at all. (even better than my G35S with very large Eibach sway bars + PSS10)
However I've driven coilover installed cars for over 12 years now which included Koni, Bilstein, KW. I think I cannot accept any car with OEM suspension except stiff GT-R...
Yes. That's correct. Stiffness is NOT equal to speed(probably less fast a little bit) but stiffness can give drivers like me more confidence, less fear and more happiness when driving it fast...