I just saw an infomercial (and I know everyone's seen these) that claims you'll lose 10 lbs. per week and have your old body back in six weeks. They give a money back guarantee, but I'm sure there are limits to that.

Has anyone every tried one of these systems, and if so, what were the results? Does the weight stay off once you lose it, and is it as safe as they claim it is?

I am currently doing slim in 6. However I am not following it how they want you to. I try to do it at least 3 times a week, most of the time it is 4-5, they say do it 6 times. I don't follow the diet plan at all, I just watch my calories. I have lost inches, but the pounds haven't come off, but I really enjoy doing slim in 6, it is 78 minutes long and I really enjoy it. I like the fact you use weights part of the time and you don't need a lot of space. I am happy with how it is going.

You might want to check out the exercise forum because I think there have been some posts about Slim in 6.

10 lbs per week weight loss? Highly doubtful unless you weigh well over 300 lbs with a restrictive diet and that is even pretty unlikely.

"Your old body back in six weeks" - also highly doubtful unless you aren't much different than your "old body". For me, I'd need to gain 40 lbs to get where I was when I was 18

So the claims are outrageous but that doesn't mean that it won't work to some extent.

They don't claim that you'll lose 10 lbs per week every week, but they do say you can lose UP TO 10 your first week. And you can, b/c both myfriend and I did.

I love the program and am seeing great results. I lose about 2 lbs per week. Some weeks I gain, but that's because I'm building an awesome amount of muscle that I've not had for a long time!
Hope this helps!

Slim in 6 is a solid workout program. If you use the videos your body WILL change.

As for the OP's question, "Will the weight STAY off?"

On ANY weight loss course of treatment, you will regain the weight if you return to your old habits. (the same is true, even for weight loss surgery.)