The fat free ones come in the smaller pots, too. Four to a pack, usually. Do check that you are getting fat free as the packaging for the others is similar - there is a little blue flash on the pack, saying fat free. There are usually peach, raspberry, and vanilla available in my Waitrose. There is also a mixed pack, but that usually has black cherry in it, which I don't like.
At the moment Waitrose has a different mixed pack of eight small ones which includes pineapple, mango, vanilla and peach They are all very nice.
I haven't tried the larger pots yet, but if they are that cheap in Tesco then I will get some as I have to go there later today.