[gemy]

I think that the best indicator is how your current dog is around other dogs. I do know that many find that bringing in a younger dog with the senior dog, rejuvenates the older dog.

As you are not dealing with un-neutered dogs I won't give advise vs a vs that arena.

And last I suppose I am more inclined to male/female pairs in the hopes of avoiding and problems. Two female Yorkies - I have heard ,but again especially with un-spayed gals can have some problems.