I'm looking at getting the Honor Harrington "mod" of this game when they release it later this year.

As I read it, it takes more RL (physics) stuff into account. This means that it will be more complex than BFG.

I would like to know roughly how much more complex it is?

I'm guessing not that much once we've got the rules down, as it states playing time to be 1.5-4 hrs, but it would be nice to hear from someone who has played both games.