I know the designer suggests against mixing both expansion in with the base game, but I honestly can't remember what the issue was. Anybody disregard his advice and try it out? Care to share your opinion?
Was it merely the fear of overkill, or was it related to deck dilution?
To clarify, I recommend against mixing both expansions until you've played with each separately enough to become very familiar with them, because jumping into a game using both can be quite overwhelming.