I'm entering the seventh year of running this Fantasy Baseball league through Yahoo. 5x5 H2H league. All prior 6 years have been with 10 GMs, but this year I am expanding to 12.
All the GMs take the game seriously, but just about everyone in the league is married and has a family (many with young children), so this is not a die-hard league, but one for those who love to play (as their time allows!) All GMs must stay active with their teams, however.
If you are interested in learning more, please contact me at mailto:firstname.lastname@example.org.