FC3 has something like five or six decently lengthed co-op missions, yeah. There were four with the default game then another one or two have been released since (as far as I know they are free of charge, too). Danielle and I replayed those co-op missions so damned much, they are just way too much fun. It's splitscreen two player for the co-op missions (and vs. missions), I've not tried for four players on the one screen but I know that with two people playing split-screen you can just join up with two other random people online and kick butt. It requires a lot more co-op than most co-op does, so it was good fun.