Runflats are not better than non-runflats... at all. It may FEEL faster because of the stiff (sporty) ride.. but it's not even in the same league as a good non-rft. I've tracked them both.
RFT: bumpy on corner entry, slides way too easily, jumps over slight road imbalances, OMG TRAMLINING - don't hit a pothole.. or else.. EXPENSIVE as all hell
Non-RFT: softer, sidewall flex means more tread on the ground to grip, WAY MORE grip, feels slower but is way faster, will save your rims when you hit a pothole, way more predictable mid-corner and exit, easier to correct oversteer.
Bottom line is that the RFT's feel like the car is on stone wheels.
6MT Sport Pkg | BMW Perf. Pedals | BMW Perf. SSK | CF Steering Trim | BMW Performance Black Gloss Grilles | M3 Rep Bumper | Muffler Delete 2.5"| Charcoal Delete + K&N Drop In | CDV Delete | Clutch Stop | Active Autowerke Stage II Tune | H&R Sport Springs | Koni Yellow Shocks/Struts | 18" Gunmetal CSL Reps | BurgerTuning Spacers | Staggered Ventus V12's | ATE Super Blue & Hawk HPS | Blacklines | GP6K Angel Eyes