Running on run flat tires was the worst tire experience I have ever had within my 40 years of driving.The stiff sidewalks transmit noise. No more bang from pot holes and my X5 is now quiet at high speeds. I purchased one of the last discontinued X5 factory spares kits, but a tow service membership is a great all-around protection whether with or without a spare. My old run flat tires lasted for 30 thousand painful miles and the lower cost of the new non run flat tires equates to 20 thousand miles to break even. This SUV is now set up to run on the highway and is not going to see much off-road adventure that would justify stronger sidewalls. This is my summer tire and so far so good. Just completed my 500 mile trip from the Sacramento Valley to the Central Oregon Coast up the I 5 corridor. The diesel motor loved the added grip and mini vans faded away thru the mountains.