My personal use cars do not have a spare tire, the cars come with a leather box containing a bottle of fix a flat from the factory.
I finally had to use the product about two years ago when I was between Lauderdale and Naples on the 75. It worked well and got me into town. I was kind of frightened thinking that I was going to have a solid brick on the bottom of the tire, perhaps the rim would be eaten by the chemical, these are all "wives tales" I had hear about this product.
The tire when removed from the rim had a white powder coating all surfaces. The tire shop, a very large reputable chain offered to repair the tire. I opted to replace the tire. The rim was wiped down and a new tire was placed onto the rim.
I was quit impressed with the product and made sure that there is a can of it in all of my vehicles.
The guys use the product on my trucks to get them to a tire shop for repair in both Florida
. To date we never have had a tire shop refuse to repair a tire that was inflated with the fix a flat.
With that said in my opinion I believe that fix a flat is a temporary repair measure.
The only negative thing I can say is that the product is in an aerosol can that does have a shelf life.. The can goes "flat" over time.
In April I had lent my zodi inflatable to a neighbor, he put a can of the fix a flat into the inflatable and it did just as what has been posted, turned into a mess. The inflatable was deflated and stuck together. I did not even try to mess with it, pulled the floor and ordered a new one. This was an expensive lesson.
In my opinion the product is great for band aid fix on tires, but will never get near my dock