They are palatable - that is to say, they don't make me gag, or taste "fake", But don't expect them to be "satisfying" either - they are designed to give you the nutrition you need, not to be enjoyed.
Of course, everyone is different and likes different things, and as you do the program your tastes will change as well. I now only have the chocolate shakes and the cranberry bars as that's I like the most, sometimes I'll have a porridge as well.
There are quite a few things you can do with the packs, to try and keep it from getting boring, but ultimately you just have to accept that you are going to be having the same things over and over and over, and that it is more than worth doing when you see the fat melting away.