The meanest chickens I ever had were RIR. Currently I have BC Marans, Buff Orpingtons, and Black Australorps. My Aussies are by far the friendliest, most reliable layers and biggest eggs. My Orpingtons are sweet, but a little more aloof and their eggs are definately smaller. The Aussies will actually coming running to me from across the yard for treats. They each give me a nice large egg almost every day. Then I've only had my Marans a few days. They aren't laying yet.