The science behind topical fat loss is well developed.
Put a good fat burning/mobilizing ingredient into a good topical gel with appropriate penetration enhancers (you need to get the active ingredient throught the dermis) and you can have a good local fat burning gel.
However, if you look at the active ingredients in the gels you mentioned, and what they do, physiologically speaking, you soon realize that they are nothing more than a diuretic -- you will reduce water in the cells, temporarily.
Avant Labs (my company) has been the premier topical fat loss company for almost 4 years.
Go to
www.avantlabs.com and look at LipoDerm-Y, LipoDerm-Ultra, and Ab-Solved.