Armies of Mayhem is a good addition to the game. From what i have seen the army lists are looking fun and are a good method of getting into the game. Only drawback is the nature of the battle scribe files. The system is not the best for a game like mayhem and the using the rooster tool feels a bit hackerish. But it is only a small hick up.
All in all it is a great package(espacially for that price) for getting faster onto the tabletop and help newcomers into mayhem.