Do You Need/Want a Rooster?

I'm in the process of getting my first flock and I'm looking to have 6 hens which will free range when I'm home in a large field.

I've seen some people say that a rooster will help keep the flock from wandering too far and will help to defend them if a fox comes snooping. But the guy I'm buying my hens from doesnt deal in roosters and has said that they're more trouble than they're worth - bullying hens and spoiling egg production (blood in the eggs etc).

Does anyone have experience with this? I'm unsure of how to proceed so some advice would be very welcome!