A long time ago I had a set of airless tires and didn't really care for them. They were extraordinarily harsh riding, and at very low speeds, like when I was playing at trackstanding, I could sometimes roll off of them. But they did work as advertised and never go flat. Once I was riding along and caught a nail that went all the way thru, came out right by the rim and was tapping the seatstay as it went around. I was by a little bait shop so I walked in and asked if they had a claw hammer or some pliers I could use to pull a nail. They guy followed me out to see what was up, and I reached down and pulled it out. I held up the nail with a smile, handed him back his hammer and thanked him, and got on and rode away. To this day I can see that man's look of disbelief.