I've recently purchased a Vandoren Optimun Alto Sax Mouthpiece. I was concerned that if I didn't like it, I would be stuck with it, but, Thomann's policy is that they will have it back if not entirely happy with the product, providing, of course that it has not been damaged or marked. Luckily, I was very happy with the mouthpiece and didn't have to return it. But it was comforting to know that I had a safety net if needed.