I've also heard that flat repair goop will collect at the bottom of the tire when the car is parked and may cause the tire to be out of balance once you get moving. At first I thought this was dumb, but then realized mounted tire weights are usually an ounce or so, and you may end up with much more tire goop than that, so I think it makes sence. I have used Fix-A-Flat successfully on a wheelbarrow and lawn tractor, where 4 miles per hour is break-neck speeds, so tire balance is less of a concern.

Not just Super White...Super Duper White...