I love them both! I have 4 cats, a dog, 2 guinea pigs, and ferrets. I have a ferret rescue actually, so some are our personal pets and others are up for adoption. Been doing this for years, and adoptions still break my heart.
I like dogs a lot better. I think I'd probably rather own a cat since they're cheaper & less maintenance (i.e.: better suited to my current living situation), but I'd definitely eventually like to have a dog again, once I get a yard & a job that pays more.