The best companion/pet dogs I've had have been rescue mutts. The worst/dumbest have been registered dogs. I've had two beagles that made my registered shepherd look positively stupid. I'm sure they actually understood more words in the English language than many campfire members.
The smarter the breed, the smarter the owner needs to be. Otherwise the dog spends its time manipulating its stupid owner. Dumb dogs seem to fare better with owners who are on the same intellectual plane. Shepherds are smart, and beagles are dumb.
