We live where it is very quiet, not many cars at all... even if a car was coming they would see me from up the road... so even if Chewy or sadie was running free and I had a problem I could more then likely flag a car down and stop them... But I am so chicken to try letting chewy off the leash.
My biggest worry would be they would go under brush or run in the woods and I would lose them. So I think when it warms up I will go to the beach to practice off leash. Chewy hates the surf, scared to death of it so there is no worry he will go in the water!
As long as there are no big dogs around it is about as safe as you can get. There's just no place to go. There's a huge cliff on one side they couldn't scale if they wanted to and water on the other side. I might start with a long rope and just bring one dog at a time. But I think I want them to feel a little freedom so if they ever had the chance to really RUN they won't feel the need to.