I have porridge too - I usually have the Hex B portion, and then half as much of it again (so 45g of oats) and count it as 3 syns and one Hex B. It's really worth the syns, it fills me up and really keeps me going through the morning, especially in the winter!
i had puffed wheat the other day and it says you can have 28g for HEb and when i weighed it out there was a lot...i was like is this for real?! and on top of that you can have 2 oat/scan bran with the puffed wheat and that only counts as one HEb.
I have several bran type cereals but when I go out for a day long hike, I would always have porriage as it is so filling, and I don't get hungry so soon.