Well, just got a flat the other day and when I got out to look at the tire it just looked like it was low on air, even though the tire pressure monitor showed 0 psi for that tire. It was very late at night and we were only about 7 miles from home. I suspected we had run flats on, so I decided to drive home. Only went 20-25 mph the rest of the way home. Got the car towed to the tire store the next day and they confirmed they were run flat tires. $305 to get another one, including installation and balancing, but well worth it in my opinion.