I origanally lost 40 with WW, slowly gained 20 back over 6 years, and am on my way back down on a system that emphasizes clean eating, unprocessed foods, and low-gycemic(like a diabetic diet). I have 5 to go.
Anyway, the good about WW is that it is very easy. Any food that has a lable is easy to calculate the points( I got so doing it in my head was a snap). Their restaurent guide is extensive, and if you do not get in the habit of using points on garbage foods, it is a very, very good diet.
The bad is it did not support my work-outs well. The emphasis is on diet, and they have items on exercise, but not the athlete training. Not their fault, the masses do not exercise like I do.
If I did WW again, I would do core. It is a much sounder concept, better for you and works with the heavy exerciser better.
The key to a diet....following it, journaling, planning, and they work. Sneak cheats in, don't write down what you eat, don't plan what you will eat, and you will fail, or if you get away from it, gain it back(speaking from pure experience).
Speaking of that, I must plan my day and go grocery shopping.