Used on cannabis. Visually really attractive. Great design. Very cool. Control button works erratically and sometimes needs multiple pushes and then you are not sure where you are. I would have said it was faulty but my friends one behaves the same way. You have to lean over it and hold it vertical to use (which partially compresses your diaphragm) when using with recommended water level or some water sloshes into you mouth when inhaling. I knew it would give a cooler smoke with less irritation but did not anticipate it would take away as much taste. Plan to experiment with minimal water level so I can smoke with it at an angle. Expected better.