One plus is that if you have a flat, you can continue to drive on the tire for ~50 miles and, thus, might be able to get to a safe and convenient place to have the tire changed. That means, of course, that you aren't stuck in the dark or in bad weather on the side of the road having to do the dirty work of changing a tire.
Another plus is that you do not need to sacrifice the space to store a spare tire. In my van, that means that there is enough room for a transmission so that I can have four-wheel drive and there is also room to store the rear seats when they fold down so that the cargo area goes totally flat. This is wonderful. I love the all-wheel drive and I love the spacious, all-flat cargo area.
OK, here are the negatives.
I have a 2005 Toyota Sienna minivan. I now have close to 48,000 miles on the van and I have already gone through two sets of tires. That means that I am getting about 24,000 miles on a set of tires. (In truth, I got 32,000 miles on the first set and 15,000 miles on the second set.)
Why did I get only 15,000 miles on the second set? One of the tires apparently got a nail or screw in it at some point early on and leaked air. We were traveling in another state and I went to a Toyota dealer who refused to work on it, saying he didn't have the equipment or training. He referred me to a local tire dealer, who repaired it for $20. The official word is that you cannot repair run-flat tires, but this tire dealer did so. After the repair, the tire still leaked, but at a much slower rate. When I got back home, I took the car to the Toyota dealer who originally had put the tires on and they claimed there was nothing they could do. I continued to drive on the tires and just filled the leaking tire with air every week or two. Finally, the tire blew after I'd put about 15,000 miles on this set of tires.
My husband was driving the car and was about 80 miles from home at the time. He turned around to drive back home and got to within about 25 miles when the tire shredded to the point where he could no longer drive. He had to be towed to the nearest Toyota dealer, who told him that he must replace all four tires, because there cannot be more than a 2/32nd-inch disparity in the tread between any of the tires. Installing just one new tire would violate that rule, so all four must be replaced. Run-flats are more expensive than regular tires.
Total bill for the towing ($175) and the four new tires installed was ~$1400.
Soooo, $1400 for 15,000 miles on the tires. Not good.
Cons of run-flat tires:
1) You are advised not to repair run-flat tires, even though it appears that you can repair them. A repair probably reduces the life of the tire.
2) It is difficult to find places that will agree to work on run-flat tires. Many places, even car dealers, simply wash their hands of run-flats.
3) If a single run-flat tire has a problem, you likely will have to replace all four tires, oftentimes even if the other three tires are in good condition.
4) Run-flat tires are significantly more expensive than regular tires.
I would implore the automotive and tire industries to come up with a better solution than the current generation of run-flat tires. The current state of affairs is simply unacceptable.
When I bought my Sienna minivan new in 2005, the dealer never uttered a peep about "run-flat" tires. I had no idea that the van had run-flat tires and I had no idea what run-flat tires were. When I found out, I was not pleased. I will think twice when I go to make my next car purchase.
