My LEAST favorite dog is a Chow.
I used to ride my horse through our rural neighborhood in Florida. There was a Rot on the corner, and the owners let him out all the time, and he was vicious. One particular day he got after us, and I just stopped the horse and said, "okay, Phoenix," and then felt the impact of the horse's hoof meeting the Rot's body. He never got after us again.
Right now, we have an elderly golden. He will be our last dog for awhile, I think. He's never bitten anyone.