You will find that you will definitely lose a lot of inches - I am 10 pounds heavier than I was previously wearing a size 38 jeans and they fit awesome. There are many benefits of the fast and since you didn't lose any weight, I really do think that there was some sort of inner healing going on and if you had stuck with it, you would've eventually lost pounds. I also believe that scales should be thrown out the window as they are the worst thing to rely on - losing inches is the real weight loss and now you know that the Master-Cleanse did work for you.
Also, I checked into this Isagenix with 2 bodybuilder friends up here in Canada at GNC and it's another "diet in a bag" type of a deal and just another gimmick and the reason you lose weight is because you have to follow the rules, just like any diet - if you follow the rules you will lose weight and it's not cheap. Now, these 2 people I've talked to have both tried it for the cut cycles prior to body building contests and they both said it didn't work and they're the most disciplined people I know when it comes to their bodies and whatever diet they are using. So something to think about.