It is my belief that if a product is a.) sold through a pyramid scheme, b.) surrounded by litigation, c.) internationally associated with liver damage* then its terrible for the body and a drain on the wallet.
You'd be better to clean up your diet and work out consistently. Even if it did work, do you really want to risk another Fen-Phen?
*Scientific studies in 2007 by doctors at the University Hospital of Bern in Switzerland and the Liver Unit of the Hadassah-Hebrew University Medical Center in Israel found an association between consumption of Herbalife products and hepatitis. 
My mother bought like 300euro worth of their crap! I looked at the ingredients and showd her, how she could buy exact the same capsules for 5$ on iherb.com.
she almost died. The products are crazy overpriced. Plus she eventually stopped using them (because she isnt a consistent person). So now there is like 200euro worth of cheap herbs laying around our house....