Hi everyone, Thanks for the advice. He does have a microchip, in addition to the GPS tracker. My main concern is not that he will not come back if he runs away, but that he could be run over by a car, since he likes to try to chase animals when we are out. Once when he escaped I was in a soccer field and I did lay down, as I was tired of trying to catch him. He did come check me out, so I agree that this works well.
The tracker does work great, and at this point it is more of an insurance since I have not had any more issues with him getting out. He is almost two now, so I guess learned a lot. He outsmarted me constantly in the first year and a half, but now I am catching up to his tricks...I hope!