I am a Realms fan and love to run games. I enjoy telling stories with rich background that players can get into and enjoy. I also enjoy the challenge of combat encounters and the mechanics of gameplay. But I believe that both are necessary, and should share equal time at the game table. It tends to be difficult to have players at the table that enjoy the challeng of breaking the game. We all know those players, and they help keep the system honest by identifying holes in the game that need to be fixed. But I don't want playtesters at my table. I want folks that enjoy the game but aren't trying to race each other to the highest attack bonus or highest damage per round.
Though I've been a player for many years, I've been a regular GM for six or seven years, running both D&D 3.5 and 4e. I have played and definitely enjoy Shadowrun, but my main love will always be D&D.