I let mine out to range and they love it! You just must always be aware that by letting them free range you are exposing them to predators, and be prepared for losses to happen. My birds love free ranging and I have a large dog who discourages predators, so my risk is a little lower than those who live in very predator heavy areas. The birds get to get out and be chickens and find and eat bugs, so personally I'm in favor of it.
I always leave the door of the coop propped open as their food is in there and they can hide in the coop. also there is a barn in the picture that they can go under. just hope it's safe enough. there is a fox around but I don't know if he could get in the coop or not. I also have ducks laying on the side of the house. figure they would get hit first if it was going to happen.