I've tried them all. They are very well done and have the perfect balance of flavor because all of them are very subtle. The only questionable in their ingredients is "natural flavors" which could mean anything.
So I wrote to the company to inquire about exactly what that means. I can't access my personal email right now so I can't copy/paste their reply, but they said something like... "We use only natural ingredients to match the flavor as closely as possibly and we take great care to make sure it's healthy" or something like that. It sounded like a dodgy answer, but at the same time, I did get the notion that they understand that people might be concerned about it and somehow, overall I was confortable comfortable with their reply.
For me personally though, I can't drink these anymore. Almost every time I do, even just a few sips, I can feel a bit of pain in my kidney's shortly after. It's the pain I'm familiar with from kidney stones. Not sure what to make of it, but unfortunately these don't work for me. YMMV.