We do need a certain amount of fat in our diets - even on a VLCD - so doing the other slightly higher cal plans AND taking Orlistat might not be advisable either. Fat isn't the big enemy people think it is (not the 'good' fats anyway) ... excess starchy carbs do the biggest damage to our waistlines if we aren't burning it off
Orlistat works largely as a deterrent to people the fear factor of the side effects keeps people on the straight and narrow. People on orlistat are allowed to eat a certain amount of fat without any problems. Someone on WS still wouldn't be eating enough fat for it to have the side effects. Exante is perfectly balanced throwing tablet like this into the mix isn't going to accelerate your losses but it's really not a good idea.