Rissóis are usually arround 8 cm diameter, but of course that can change... The ones with shrimp are usually quite spicy, so I think economisto would love those ones
They are best eaten still warm, with a cold beer and a plate of black olives!
At my grandmother afternoon snacks we had the minced meat ones (which included just a little bit of chourico), which were really good (I have to confess I have never eaten cheese ones, but it sounds good!)