Most of my cats seem to have been great judges of canine character. (Possibly human character too, but that's a whole other story book.)
My first cat, Mix - the one that looked like Buffy's cat Polly - was ace at dogs. I had a friend with a
very large,
very bouncy GSD. First time he visited us at home, he spied the cat asleep on the back of the sofa at the far end of the next room and promptly launched himself at a gallop in its direction. Halfway across the second room, the cat opened one eye. The GSD skidded to a halt in its own length, looked sheepish, turned away and skulked off back from whence it came. Mix watched him leave, flicked the end of his tail just once, closed his eye and resumed his snooze. Maybe there was just a hint of a smug smile playing around the corner of his mouth...