I've had 4 punctures in 2 years. I didn't trust plugs so the first 2 times, I replaced the tire. Considering one had barely 500 km on it, this hurt. When the 3rd puncture happened, I got fed up of throwing out tires that still had a lot of life left so had an internal plug installed. It took 3 tries to get a plug that was airtight but the last one came out of the carcass about 1/8" to the side of the puncture. I figured that meant there was internal damage I couldn't see so changed the tire. The 4th puncture was dead center on the rear tire, a tiny 1/16" dia finishing nail. I don't know how it even managed to get in the tire. Anyway, it looked like the perfect candidate for another plug so gave it another try. This one also took 3 plugs before we got one airtight but it started leaking about a week later, maybe 3 pounds pressure a day. As there wasn't that much time left in the season, I decided to just keep filling it up every other day and will replace the tire over winter. I rode the bike reasonably hard (for the street) and was never worried the tire would blow or anything. Still not worried about a blowout but considering the hassle I've had with plugs leaking, not sure if I'd bother trying plugs again.