I have a can of the tyre weld myself but haven't yet needed to use it.
Its ok for a get you home, its not designed to be a permanent fix for the tyre. Some garages may also try and fob you off by saying because you've used the tyre weld the tyre is no good, this is utter b******s. All they are trying to do is scare you into getting a new tyre and also its probably because they have to clean the tyre before they repair it.
If they turn around and say that then take it somewhere else becasue they are no doubt trying to rip you off and will try it again in the future.
I know this from experience, i used to work for a well known tyre/mechanic firm and we regularly used to get people who had tried to get their tyre repaired but was told it was no good when it was totally fine (apart from puncture of course).
Obviously sometimes you do get the decent place that will tell you how it is and so i think its probably best if you get a couple of opinions before settling with one of them.
Just thought id tell ya,
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