I think that goes for the majority of Border Collie's. I thought Milo had a brilliant temprement but Jayjay is just perfection. Like every breed they have bad owners and some of them do turn out aggressive but based on my experience I think it must be very hard work to turn a Border Collie aggressive, but then again that goes for every breed. You can't pick a breed and say they are any more aggressive than another breed, there are aggressive dogs in every breed, the majority of which is down to bad ownership. It just shows what level of morons we are dealing with. (