I'd say 9/10 times you'll have a bubble on your sidewall.
stock RFT's suck!
2nd day of owning the car I hit a pothole (raining/dark) and my car too, shuddered like something terrible happened.
Pulled the car into my garage, noticed a nice size bubble in the tire.
Yeah... they suck. Never will I run RFT's again. The price of the Bavarian Autosport spare tire kit will pay for itself if you have to replace a single RFT.
07 SG 335i