Fix a flat will put all kinds of junk into your tire and some shops won't even touch the repair if you've used a repair kit first. What kinda repair kit are we talking here?
Also, in case of blow out a repair kit won't help ya
NEVER EVER use fix-a-flat. Why? It's called TPMS ........ use that junk and you'll end up replacing all of your TPMS with each tire affected.