Anything more than 3 people in a group gets tiresome very fast, as if I can't keep up. I find that three is the magic number here; away from the awkwardness of 2 and less than the exhausting presence of 5 or 6 people screaming "yo moma" jokes.
(That's my experience with HS at least)
I'm not fond of total emotional detachment in discussions and group settings but I don't really like SUPER LOUD GATHERINGS WHERE PEOPLE LAUGH AT EVERY SINGLE THING HAHA HA.