I can absolutely talk about both angles, cause I have one of BOTH.
Hamish was a surrendered dog, who was about 4 when I got him. He was a "runner" and I really believe his family was abusive because he was scared of feet, ran a lot, but he was such a grateful, lovely creture who just adored my (wait for it) 171 pound Great Dane. The were the best pals. Phantom died at 8, but while they were together the were the best buddies in the world (helps that Hamish weighs 19 pounds!). He was housebroken and played fetch, loved me, followed me around so much my daughter nicknamed him "my doggy husband".
Fergus I got at 13 weeks. He is my heart, my protector (he really does bark at everyone canine or human who comes near our chair!). Everything his is, or isn't, is MY fault. Housebreaking has been just LOADS of fun. I don't miss it at all! and his obedience is non existant. But I got puppy kisses and he and I bonded in a totally different way.
My next one? I will let fate decide. If my breeder has a litter, maybe I'll get one of his cousins....or if I find a rescue (I do a lot of rescue work--out vet is a registered non profit rescue) that needs ME and fits into our family, then that's how I will go.
What I will NOT do: go to a pet store. Or a byb'er. or order a dog off the internet.
but I will leave the rest of it to fate.
