I have a small and a large Knot-a-Leash both around 10 years old, both starting to show a bit of wear. Neither leash was at the end of use, both had a bit of wear at the knots I had tied in them. I bought 2 new leashes and they are of the same outstanding quality of my first two. These leashes are tough, comfortable, and will probably last me at least 10 more years. Other than the quality and the clip, the thing I like most is the ability to tie the leash at points that I need. For the collar I tie 2 knots, one for a close heel, one for a more relaxed walk. For the harness I have one knot for a relaxed walk. The knots give me extra grip for times when I need more control, like when a herd of deer cross our path and Mario goes nuts. I love these leashes, they aren't cheap, but they endure. They are worth the price in every way.