I have used optifast and for me was the best way to lose weight. I have a friend who tried it and couldn't stand the taste so didnt last a day on it. I lost abuot 10 kg in 3 weeks. That was just having the shakes and a small amount of vegies at night. I think if you can get past day 3 and keep yourself busy it is easy to stick to it. Coming off the shakes is difficult because if you go back to the way you were eating before you will just put the weight back on. When you start eating again you have to eat well (like weight watchers or something like that).

I went away for 3 weeks to my parents place to start and when my hubby saw me after 3 weeks he couldnt believe it. It does work if you can stick to it but it is definately not for everyone.

I dont know about Celebrity Slim. Seems to be the same sort of thing as Optifast. I must add that Optifast is the only shake that I have tasted and liked. I add a lot more water than they say and I also have to drink it ice cold.

All the best with whatever you chose to do.