What experiences have owners had with sidewall problems, etc. where the "gooey" stuff could not seal the leak. Is it anything to be concerned about? I have the all-weather conti tires-only 4000 miles on them.

Am greatly concerned since ready some of the comments from others and what they experienced when they had tire problems.

Would appreciate any input or advice since I am concerned as to what I do if my wife and I are traveling and the problem occurs.