the double tube stethoscopes are both better and worse than single tube. The problem with the double tube is that you pick up more artifacts, such as the tubes rubbing together. The high dollar littmanns actually have double tubes encased in a single tube, so you get the best of both worlds with neither of the down sides. Has anyone found any super cheap insurance? I'm just looking for the cheapest insurance that the program will accept. I don't plan on using it, and don't really have any money, even for the cheapest insurance.