The Epic Edition is worth the money. The statue is large, detailed, but plastic, something I didn't expect.
The octus medal is the other most prized item, I don't really use multiplayer so the skins were useless to me.
The personal effects are ok to read, as well as an insightful book about the creation of the game.
The game itself does have several twists, but there is nothing that is OH MY GOD epic about it. But then again, what games really do explode on finishing? None that I can think of, but it is way better than the predictable Halo 3 ending. In my opinion this game is a little over Gears of War 2, I loved them both.