I actually used this stuff as a teenager. My aunt and cousins were on it and swore by it so my mom purchased some.
I remember it tasted awful and did nothing for me. Unless things have changed, it's a shake and pill diet that, like most "fad" diets doesn't really work. You might drop some weight in the beginning but those shakes were NOT tasty and the "fill you up pills" definitely did not fill me up. By the 3rd day I wanted a hamburger so bad I could have slaughtered the cow myself. Shakes are boring and it's much MUCH harder to stick to a diet that's boring.
Use the money to buy yourself some quality food and cook instead! Honestly the best diet is the good ol eat less/exercise one that everyone hates (it's hard
I hate it so much hah). But it works far better and is cheaper and better for you.