i have had both a rottweiler and a pittbull so from experience i can say it is most deff how you train your puppy i had them both since 8 weeks old so i had the, from the start and traingin them the same way i can say both are not mean dogs but when it comes to there owner being in trouble or if they sense harm a pittbull is way more dangerous and will do anythin to make sure the owner is okay, the rottweiler is protective to but pitt wayyy moreee!! it in there nature!!