I have one sort of like it. I'm retired truck driver and when we got a flat coming into the yard I would practice on it before the tire guy would get there to the fix tire right. Maybe did about 3 dozen total. So here is my take on Truck tires, not RV or car, but might give some insight.
Sometimes getting out whatever caused the flat is the harder than putting in the plug. Sometimes I couldn't get the plug into the hole. I went and bought a file type thing that is made to make hole bigger so you could get plug in.
Ok, one day our Corp big wheel safety guy sees what I was doing and read me the riot act. Told him I was just practicing on his stuff for my own stuff. He verified that tire guy was called and I wasn't fixing his equipment. He explained basically that he thinks they should be "outlawed". His reasoning was...Can't see inside damage, high failure rate etc. His biggest complaint was that people after plugging a tire don't get it fixed the right way and keep using the plugged tire, which is not the best idea I guess.
So after becoming familiar with them, I put my handy kit behind the seat of pick up with the intension of using it for "just in case" repair. Just to get to the next place to get tire repaired right.
Years later maybe 8, that day finally came. Flat on RV trailer, left rear. Got out the kit and to my surprise all the glue and the plugs were dried out from sitting behind the seat. Sort of popped my bubble. Looked up Les Schwab and one was 8 miles away. I drove down there going about 35 on side streets and they fixed it for free.
2003 Majestic 23P... Northwest travel machine
2013 Arctic Fox 25W... Wife "doll house" for longer snowbird trips
2001 "The Mighty Dodge"... tow vehicle for "doll house"