I met many of the actors on Eureka at Comic-Con. They were all quite pleasant and friendly. The actors who play Jack Carter and Nathan Stark seemed like pretty close friends, and constant comedians. Both were very charismatic.
The actor who plays Fargo, whose real name is Neil, is quite cool. I hung out with him for a decent amount of time. He is a comic book collector (or was, but has not had much time for it the last year or so). He's from a town in Canada not that far from the town my wife is from, so they chatted about Canada for a while. He struck me as someone any of us would feel comfortable hanging out with. Very personable.