I trust this is a great product based on the integrity of the person who recommended it, but something in it aggravated my health problem. So I can't use it because it causes pain. It may be the flavoring, but I don't know. I've used powdered amino acids before with no trouble, and the only difference as far as I know is what's in it besides the aminos. Sorry! I can't comment on quality because I could only use it a couple of days.