I have just attempted it, depends on which one you are trying. There is the lose 10% deal where you just replace one meal with Special K, eat lunch and dinner as normal and replace any snacks with Special K bars or the one where you just do breakfast & lunch as Special K and then a normal dinner for a larger weightloss.
Aimiloo is right, there isn't enough food (or not the way I did it) and the special K bars are crap (Fitnesse ones are nicer) but they are so sugary and cardboardy. I did drop about 5 lbs, but I found it hard to sustain and although I have a fridge at work, I don't feel like soggy cereal at my desk!
I get the impression you don't work (I could be wrong!) I think it's easier if youre at home a lot more, that's when I just did it after knee surgery because I couldn't exercise as normal.
Good Luck though, I think any effort deserves support.