No. It will waste your money, unfortunately. The only way to tighten your tummy is through your own core and ab-resistance work, and the only way to get rid of the 'flab' is to lose bodyfat..... OR if you're down to a very ideal bodyfat % and still have the 'flab' then it is likely extra skin. Still wouldn't take care of that. You have muscle, fat, and skin, and they all work separately, so that's why you could do a million crunches and still feel like you have a flabby tummy if you haven't lost the 'fat' that's layered on top of the muscle.
Cardio, core/resistance work, super-clean nutrition. There isn't anything that speeds it up.