It works if you stick to the plan, and if you want to keep the weight off you really need to follow their Transition plan to get back onto real foods. Regain can happen fast if you just quit and go back to eating what you used to eat. The food isn't all gourmet, but most of it is decent enough to make it through a period of dieting.
Lost 103 pounds, regained 60+, taking it off again.
*Never Give Up!*