the owl competition in Australian tf2 uses halves like esea and plays 2 maps per round (each round lasts 2 weeks). Both maps are first to 5, or 4 in the case of koth. We have had other competitions that only allow a 30 minute time limit and are first to 5 however.

The 5 round difference rule could create some interesting situations for teams and make the game more exciting, giving the losing team a chance to make a comeback. However, in a 30 minute time limit, getting more than 6 or 7 rounds played is very unlikely and the team that pulls ahead could just turtle to win.