Update..
Great news Rob,
I was on Medifast, I am assuming that it will be alot like the opitfast program. Make sure to ask if you can add extract flavorings to the shake. I found adding a little peppermint, almond, Raspberry or other extract to the shake just to give you a different flavor. I also found that mixing it in a blender with ice and water help quite a bit.
I found that the first day of two of the liquid diet was the worst for me, I craved anything that was not bolted to the floor. Just don't cave in during the initial period and it becomes so much easier. Believe it or not after those first few days, I only felt hungry if I was running real late for one of the shakes.
I was able to loose 45 pounds in just 4 weeks and I am sure you will also do very well. If you have any questions, feel free to drop me a line.
Jim