I have nothing but good things to say about the product. I've used it since it was first developed, and find it very effective, especially in combating the dryness of winter and sun damage of summer. I can even use it on the gig or in the practice room without affecting my playing. I highly recommend it to my students and fellow musicians, and carry tubes in my car, trumpet case, and various other convenient locations. It's nice to count on Sam Ash to always have it in stock (which it is). My only problem is the occasional disappearing tube, thanks to my son (the guitar player) who takes the "for people with lips" slogan to heart, and is not above permanently "borrowing" mine from time to time!