I have had similar experience as you, they free range just fine, get along with all the other poultry, I have F1 and F2, the F2 have bred true, lets see how the F3's do, The second generation has grown and finished out at the same rate and weight as the F1s, so i am hoping for a sustainable bird for the farm, they lay like laying monsters.Gosh, i've had quite a good experience with them. I got a few Pioneers from MMM. Two roos and a hen. I love them. They're big and grew fairly fast, but didn't have leg or health issues like some of the CXs i've had in the past. Mine are docile and pretty friendly. They don't fly and aren't stupid, IMO. They're also free ranging well. They get along with the other chickens just fine and haven't shown any aggressive behavior. To top it off, they are pretty to look at and have unique color. I just ordered four more so we'll see how the next ones turn out, but so far, I am really liking these birds.