by Mordus
Since you already enjoy Eclipse, I would say get the expansion.Runewars is a longer, deeper, more tactical game for fewer players.
Eclipse is a simplified 4x style game that is easier to pull players who aren't into super in depth strategy type games. I personally believe Runewars is the better game, but at the same time it's not for everyone. If I'm trying to introduce new players to the genre, I'm going to use Eclipse. It has a much broader appeal.