I went to my tire shop today about a slow leak. I went down the street to the hardware store for a minute; came back to find that they had found a nail in the tire and had plugged it. I asked if it was patched, too, and they said, no. They use a plug that mushrooms on the inside, so that a patch is not needed. I asked if they had balanced the tire, and they said, no, that it wasn't necessary. I'm not sure I would have had things done this way had they asked me. Is what they did acceptable? They say the plug should be good for the life of the tire. The charge was $15.