I have been using Quel for about one week. I have finished my third bag and I can only say that the experience is very positive. I was a bit worried about the taste, but it is very nice, nor strong or too sweet, just nice to not get tired about drinking another one. I don't feel any real difference respect "normal" food: I don't feel exhausted (and I do a lot of exercise), hungry or any other side effect (even... ehem... I am going to the bathroom as same as ever). I usually take 2 queal foods per 1 normal one, and I am very happy with than combination. Just 2 small complains: - The bottle: at least mine can not close very well after a couple of uses (I had another similar from a sport shop that it is more practical) - It is a bit hard, at first, to guess how much powder you must use. I have found that around 4-full measurements (with the spoon they provide) it is almost perfect.
Overall I am very happy and will continue using it.