Cats, easily. I love dogs, but there are so many inconveniences to deal with regarding dogs--and believe me, I know, being a door to door salesman. I never have to worry about my cat keeping the neighbors up at 1 AM. I don't have to talk over cats to be heard. Cats don't jump up on me and cover me in saliva. I don't smell like cat all day after playing with one. I don't have to let the cat out to crap all the time. The list goes on and on.