I must respectfully disagree with this. If it's a nail or a small screw, then what damage are they going to be inspecting? We already know it has gone through the tyre. To me this is completely unnecessary fear mongering. I would bet a lot of money that you could warm and pressurise a motorcycle tyre that has been repaired with a self vulcanising string and the tyre would explode before the plug blew out. Maybe it's different on a car with more shearing force as it goes around a corner, I don't know but searching the internets returns not a single instance of a motorcycle sticky plug, blowing out as if you used a piece of cork. Yet there are very many stories, of these sticky plugs lasting the life of a tyre from new and never losing any pressure at all. When you pull the string out you're left with a little bulb in the inside which makes it as good as impossible to blow out.
That is totally fair. Like I said I trust plugs. I was making the nanny recommendation of the safest option. I will continue to trust plugs, because I am too cheap to replace a tire with life left in it.
Not sure I would fully trust those mini plugs, heard some horror stories of them letting go after as little as 10 miles. I always use vulcanised strings to plug a tire. Just plugged my T-bird 1600 rear tire last week with a screw in it and it hasn't lost a pound since. Had a plug in the rear tire of my GSXR11 before and had no problem doing triple digit speeds with it. A simple cheap repair kit and small compressor and you never have to worry about getting a nail in your tire again.
My personal experience with mushroom type plugs has been very good. I seem to manage to get a sheetmetal screw or roofing nail in a new tire within the first 30% of a tire's life (especially Pirelli Rosso's ! ) and have successfully used a plug to seal the hole and claim a good portion of the tire life back. They rarely lose pressure, but you always have the option of using a bit or tire sealant on the replacement plug if you need to. I've also used the string type in the past with success, but I prefer the mushroom type as it doesn't necessitate carrying fresh glue around with you.
You should not need to carry fresh glue with you as the string type are self-vulcanising so they will bond to the tire without any need for additional glue.
Well it is still holding and I have done few trips to work 50mls; I put some Gloop in for peace of mind last week.
Maybe I should take another look at those. The last ones I looked at buying included a tube of glue, and recommended using it. What brand do you use?
The current one I have was just a kit I bought on Amazon. https://www.amazon.co.uk/gp/product/B083QFXYTV/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1
safetyseal.com I've used them didn't leak at all for the life of the tyre. They seem to be the best self vulcanising and they are a jaunty brick colour. Available on feeBay.