Review (4/5): Messy
I really love using creams like this with my sweat trainer. No, this is not needed and no it will not help burn fat. It does help enhance how much you sweat though which helps with any added water. I really like this one as it works well.
It is a jar as noted and can be very messy. I prefer the stick formula, but do prefer how much easier this is to rub on though.