I have plugged several. I would recommend a plug/patch but you have to remove the tire which can be expensive if you let a dealer do it.

 

I picked up a nail in my fresh new rear tire, I saw it when I was going home from work, walking up to the bike, it was a roofers nail dead in the center of the tread, no telling how long it had been there, absolutely no change in tire pressure when I checked it. I roide it home, then the next morning to the speed shop down the road that does allot of high performance work on exotics and bikes/race bikes. He said he would plug/patch it since it was dead center, but not if it would have been off to the side. Anyways, he said the tires like new and a plug patch would be fine so long as I wasn't heading to the salt flats or anything (sarcasim) so I said go ahead. He took of the tire, razzed up the nail hole and the rubber inside the tire around the hole, and put in a mushroom plug, then backed the plug off with a patch, put some goo on it and used a heat gun to cure it, then trimmed the plug off near flat on the outside, re-mounted the tire to the wheel, balanced it,then on my bike and I was out the door. Cost me 50 bucks, mostly for the wheel removing and all, would have been 20 or so if I took them the wheel I think. Anyways, that was 4K miles ago, and lots of those miles were at a good pace, so thats my experience FWIW.

 

Ditch the plug.

At the very least, do a patch/ plug. This method puts glue on the inside of the tire where the patch will cover and the plug that's molded into it reinforces a proper seal.

I have an extra tire I use once in a while with a patch/ plug and it's handled repeated 130 mph blastsjust fine.

Dismount the tire and take it to a tire place. See if you can hit up one of the techs for a freebie and offer a coffee in return.

 

As I am the king of procrastinators, I've ridden on a standard plug for quite some time. You can get them from Autozone, Kragen, etc...Using rubber cement will help them greatly. I wouldn't do any long rides, racetrack, burnouts, but it's a good until you have the time/money for a new tire, (which definitely should be a top priority).