I'm a confirmed horse nut from my teenage years (I had to board mine in the early years when I could finally support my horse habit). I'm a long time cat owner (I had pet rodents and many fish as well) but after I finished school, married and bought a home with small acreage -- I was finally able to have dogs and just about any critters I wanted.

For me dogs win hands down!

In one package, you have portability, a cuddler, loyalty/love, a guardian, a companion and interested partner, one who watches while you sleep, who can help carry things for you (help me keep my balance, I'm disabled), work (oversee livestock) and play to make me laugh, alert me to danger (on coming car, I'm deaf)... and they accept all the same benefits in return. For me, there is just no comparison to the versatility and the partnership one can share with a dog!