The only breed that I knowingly have a prejudice against are Quarter Horses. They scare the pants off me. They are SO FAST!!!
Once I was trail riding on my Arab with a friend, who was riding his big, young, tall, red dun quarter horse gelding, when a deer came crashing out of the ticket, right at us.
My Arab jumped a bit, but that quarter horse spun in a total 180 and took off back to the barn so fast that he was out of sight before my friend hit the ground. Knocked my friend right out. I remember it like a cartoon: a horse running flat out with his legs just blurry scribble, while saddle and rider are left behind suspended in the air... In reality, the saddle stayed on the horse, but I don't know how. I never saw anything like it before. Give me a nice, quiet, slow Arab, or an OTTB!