I have a friend who has followed this plan. She even worked for the company for awhile. It worked very well for her. Her husband, who did/does not need to lose weight follows it with her, and is happy with the food choices. She is looking much healthier since choosing this way of eating.
That said, I tend to think more along the lines of Susky2. Why pay for something I can do on my own? But I do not have an addictive personality; once I have learned the "whys" of something, and accepted that, for example, eating a certain way is better for my health, I am able to follow that path pretty steadily. Others, I know, cannot always do this, and perhaps the strict guidelines of this program are better for them.