Should you include daemons in your chaos marine army?

Answer 1

Lesser Daemons are 2 less points than a Chaos Marine, and have roughly the same stats with the exception of a 5+ invunerable save. They are best used to tilt the balance in combats; they should not be deployed without support. They are one of the few units which can charge after deepstriking, and can be used to ruin opponent's plans- however they have to be used correctly to be worth it.

Greater Daemons are another story. At 4 wounds, Toughness 6 and a 4+ invunerable they can almost always get their points back and smash enemy units with ease. They enter play by possesing a model in your army. It's suggested that Greater Daemons are used more regularly than Lesser Daemons due to the fact that their stat allows them to deal with many varying units.