I have five hens and one drake. The advantages are fertile eggs I can hatch, and protection, my drake will stand in front of his girls and he usually makes them calmer. My favorite ducklings always seem to end up being drakes. Maybe they endear themselves to us so we keep them around. Disadvantages, he picks on certain girls, especially in the spring. This lands him in drake jail (he stays in the pen) for a length of time and is a pain.