A former neighbor has one for his large yellow lab and it works for him. He lives on a small lot and the fence encompasses a small area. Like you he didn't want the dog to run into the road.

Buddy stays away from the fence and knows his limits. I suspect a lot of it depends on the dogs training and relationship with his/her master.

My neighbor bought the insurance policy with it (not too expensive) and it was needed. Power surge took out the control box and it only cost 5 dollars as opposed to the 300 the box cost.

Good luck with your fence.

Anne