The 328i I tried was running on 18" Goodyear EfficientGrip RunOnFlat. To be totally frank about it, was the best RFT shod BMW I'd ever driven.
My exact comments were... as posted at the time.
As I got going on the A9 on the way up to the M90, it all felt so good I almost failed to give the driving feel any attention, as it felt so natural. The suspension on the optional 18Ē efficiency RFTs was in a different league to any RFT car Iíve ever driven. None of the niggles of the F10/11 cars I tried just after their launch. On a sideways tangent, I swapped my 330dís winter tyres just yesterday, so had my summer set on for comparison, had just driven 90 miles in temperatures from -2C to +9C, so a good spread of feel and had got used to the ride quality again, after driving 275 miles on the winter tyres over the weekend, on some pretty poor roads. So back to the F30, the ride was quite supple, temperature was climbing, now over 12C, I ran a few cats-eyes to see how we compared to my car, the RFTs were thumping them out with less drama than my car. Top marks for a good start.
BTW, I'm running 17" non RFTs, both summer and winter on my E91 330d. I had Bridgestione Potenza RFTs when I bought my car new, so well know how a Bridgestone "doesn't work" on UK roads.