Being a Böhm clarinet player, I bought this ligature to try to emulate the German sound on my French clarinet. It turned great! The sound is mellower than most metal ligatures.
I would recommend this product to all clarinet players to experiment with, but it does work better on German and Austrian clarinets because those mouthpieces have grooves on it specially designed for the purpose of wrapping it around.
I have been playing on it for some concerts on different mouthpieces and both with great results. Some time on a Vandoren BD5 and on a Vandoren M30D (which is based on German system mouthpiece for French system clarinet, having the grooves on it)
The only con I can mention is that because of its wrapped "nature", it can be difficult to change between reeds in the middle of a performance, but I think that time with it will give you dexterity to swiftly change.
Over all, this is a great small and affordable piece of equipment that will allow you to experience with other colours for your sound and both amateurs and professionals can benefit from it.