A healthy dog is the most important thing to me. My dog is pure bred, but the breeding wasn't as great as you would think. She has a lot of health problems that came up in the beginning. We worked closely with the vet and were able to make it past them all though and now she's as healthy as a horse.
She's a great dane so she's the size of a horse.
Though there are some characteristics of breeds that might be bred out from time to time, a mixed breed or pure bred can make a great addition to a family. Sometimes the quirky characteristics that might pop up will be pretty entertaining as well.