I've only had 4 flats in the last 2 years. If I were riding in conditions that resulted in a greater frequency of flats, I would probably agree that the cost is greater than that of carrying a hand pump. As it stands though, I don't mind the $3.00 cost for a cartidge compared to always carrying a hand pump in the pocket. I ride on 25 mm tires, and one seems to pump it up very well - I'm not sure of the actual pressure the tire is running at, but I wouldn't mind riding it home, however far the distance.