My supervisor has two Jacks - her latest one was and is a real handful. Her first Jack is a real sweetheart - not too destructive and pretty mellow. So I guess it all depends on the personality, I actually know someone who has a really naughtly Golden and they are the sweetest dogs in the world. I'm just a firm believer that the dog is as good as its owner wants them to be. Hope my Chihuahua grows up to be a real nice dog. We're having biting problems now - she's really nippy. Doesn't mean to bite hard, but sometimes she does.