I just road forced my two front tires today. Because life is short and I'm curious if it's all hype or a rip. I got Brand new Michelin Pilot Super Sports 18s.
The runout was 0.007" roughly and they got it down to .004". They said this number is so small, it wasn't even worth road force balancing. They said it has to be around 0.14" to feel something. But they agreed and rotated the tire on the rim to a better position. Everything else checked out fine, lateral runout and such. So my rims aren't bent or anything.
On the freeway at 90MPH, I'm getting slightly less vibration now. Either it is just psychological or it really is better. I don't know. Would I spend the money again next time? It's not that it's THAT much more in costs... but it does feel better knowing that your tire and rim are physically balanced in the best arrangement possible...
2009 335i 6MT - M-Sport - All stock