In terms of earlier discussion, Tribes is a game that I would consider realistic, but not detailed. It is self-evidently not detailed, since it has only two turns per year and abstracts away most detail. On the other hand, it is fairly realistic--not completely so, because there are a number of inconvenient ways to die that the game doesn't represent, and the probabilities of various things may be a bit off--but realistic in the sense that it is easy to imagine events to match the outcomes of the die rolls. (This may be a weird sense of the word "realistic"--is there a better name for this property?)
Anyway, we played Tribes for five hours or so. For much of the game, we had an extraordinarily successful tribe, but then at the end, we ran into a famine that killed 13 children of 17. Ouch. But we were still pretty successful as a tribe.
I found myself playing according to the personality I've used when demoing Tribes at cons, in which I play more for the good of the tribe than for my own good. This probably helped bias the whole group towards a more communist system. It would be interesting to try a game with people paying more attention to their own good and being less generous towards others.
We didn't get nearly as much into the roleplaying aspects as some groups I've played with have. In particular, other groups have shown a lot more roleplaying for sexual propositions and great hunts.
One of my regrets about Tribes is that it takes so long to play a game that it's hard to see the effects of player strategies and tribal laws. (In fact, every game I've played has been by players just learning the game rules, and saying "let's make up the laws as we see the need.") I wish it were possible to play in, say, an hour, so that you could play several games in a day and experiment with different rules.