I had an old Sigg bottle for years that worked perfectly, but a few months ago I lost it and had to replace it. Naturally I wanted another Sigg bottle. Unfortunately they now have this new BPA free lining (which I would love if it worked), but within months the lining started coming off of around the inside of the mouth. Now the cap doesn't stay on tight, and if the bottle is on its side it will leak water out. It makes me really frustrated, there's really only one thing a water bottle needs to do and that's hold liquid - which my fairly expensive sigg bottle now fails to do after merely months of use. I'm not sure what I'm going to buy to replace it with, but I know it won't be one of the new Sigg bottles.