Who were Buck's owners and which was the best?

Buck has quite many owners before he finally surrenders to the wild. His first owner is Judge Miller. He and his family treat Buck well. Buck spends his days playing around the home, “hunting with the Judge’s sons," or going for long walks with the Judge’s daughters. Manuel, an assistant gardener to the Judge, then steals and sells Buck to some dog traders, who finally sell him to Francois and Perrault, who work as mail couriers. These two are generally good owners who, however, do not hesitate to make use of the club or whip to “demand instant obedience” and service from their dogs. While with the two, Buck is transformed from a “civilized” dog to a dog that understands the “law of club and fang.” He learns how to pull a sled, keep warm in the night by burying himself in the snow, and how to protect himself from other dogs.
Next, Buck is passed over to a Scotch half-breed who keeps him for a short time before selling him to Hal, Charles, and Mercedes who are, by far, Buck’s worst owners. The trio has little experience using dog sleds on the trail, and end up losing almost half of their dogs due to this. They are cruel dog handlers, especially Hal who continuously whips the dogs. Buck is rescued from the trio by John Thorton, who is the last of his owners.
Buck adores John Thorton who is a loving owner and excellent dog handler. Even his dogs are described as “having the kindliness and largeness” of their master. John takes care of his dogs as if “they are his own children.” In fact, Buck so adores John that he cannot stand being away from him. Thus, John Thorton is the best of Buck’s owners.
When John Thorton dies at the hands of the Yeehats, Buck finally surrenders to the “call of the wild.”