They are cute. :). First learn about the breeds and their energy levels. There are specific handling tests. This site describes them well.
http://www.dogbreedinfo.com/articles/puppytemperamenttest.htm
Your training is just as important as the pup's disposition, if not more. Remember, you're raising a dog - not a puppy. Do you want a huge St. Bernard jumping on visitors? It's cute when he's tiny, but ...
Discipline is not mean. It's teaching. It's a gift of love.
