I really like the idea of no air tires.. I don't even have my engine kit yet but I'm already worried about flats because I'm not mechanically inclined and the first time will be rough. And right now, I don't even have a pump yet... Bought a little toolkit at Walmart but I think I'm going to return it. The first time I needed to use it, it didn't have what I needed to work on my bike. The no flat idea seems great. Wish someone had already bought them so we could know what they ride like. Does anyone know how much the airless tires cost?