If you are really that concerned, buy 1 - 18" wheel and tire and keep it in the trunk as a spare. In an emergency, it will work on either the front or rear.

Keep an eye out on ebay. There are wheels and tires available regularly at semi-reasonable prices.

Of course, your trunk space will go to about zero...

Then again, the only time I had a problem, I blew out a front AND a rear. So this solution would still have left me with the tow truck!!!

:lol: