When we first got Jack, our Cattle Dog - the foster mom warned us he was a runaway. We did a LOT of training on his recall (I can whistle REALLY loud) - then I bought a good 1/2-mile range electronic collar. Basically - if he left the yard (mine is fenced on 3 sides - but open to the lake) - I'd whistle twice. If he didn't show up in about 30 seconds, I'd hit the button on the remote. It only took about twice doing that - and he started coming FAST on my whistle :-) Eventually, he learned to not leave the yard.
I guess I'd rather have a dog stick close by, than be able to track them?? If your dog runs - the GPS might tell you where to find the carcass after he gets hit by a car or shot by a neighbor.....