My experience involves mostly American Game roosters. Over the last ten years I have been working with American Dominiques and their hybrid with American Games. As kid we kept RIR, Barred Plymouth Rock, and White Plymouth Rock although those seldom reached maturity on the male side. Those that did were good natured although birds of same stock kept by neighbors were not pleasant. Difference I attribute to husbandry methods. Neighbors then and many people I see now interact with roosters in a manner that is not allowed here. No aggression towards rooster and their charges nor recoil if a bird pecks you.