We had a pit mix (with aussie cattle dog) for a while. Very smart dog, though a little high-strung when it came to thunder storms and fireworks. Had some leash aggression issues when it came to other dogs (not humans), and in the off-leash park tended to be the enforcer of order (never aggressively, just ran interference every time another dog barked or growled).

It did have a couple of issues with the cats, in a "you've invaded my personal space" sense, but it was just a quick growl and done. But when he did it the second time to my young daughter (now 4 -- she wasn't always gentle about petting the dogs), it was time to get him into a home without young children.