Was just curious if anyone could answer this question for me? I'm looking for a new dog am thinking about one of the following 4: BullMastiff, Cane Corso, Dogo Argentinia, BoerBoel. If I were to get one of these as a puppy what would be the ideal age? Also if I were to get an older dog that needed a new home would they be able to adapt to me as a master or typically would I be getting a more stubborn dog?