The first ones I had, chicks from a pair of McMurray birds, were the worst chicks I'd ever had--flighty, even vicious. I called them the Vampire Chicks after the four of them plucked every back feather and some tail feathers off seven of the Speckled Sussex chicks in their grow-out coop in the course of two hours one afternoon. Sold all four, even the pullets. Swore off the breed. Even the parent pair were culled later for aggression.
Last year, seriousbill talked me into doing a fertility test for her cockerel she was growing out. She'll tell you that I was very hesitant at first, but she promised these would be different. They were very different. They are the most curious, friendly, in-your-face babies and they grow up to be very friendly, inquisitive adults, too. Mine have tons of personality. A couple want to be picked up. My rooster likes a chest scratch every day. I hatched some last year and this year, this year's were from different birds of hers, and both batches were terrific. One of the girls, Maxie, is one I call "Mouth of the South", but the others are fairly quiet. Terrific foragers and great layers.