I have a friend of mine from work that plays game battles. I've gotten online with their crew a couple of times in public lobbies on mw2. They have been playing together for about 5 years. These guys annhilated everyone we played against. Right now he is playing 2 v 2 and 3 v 3 on gamebattles. I think the 2 v 2 team is ranked number 14. I have watched some of the games on his recent games list. it is pretty intense. He told me the closest gameplay to gb is to play barebones competition. I am sure there are all skill levels that play.