Purebred vs. non-purebred

Question
I'll attempt to be brief:
My wife and I are in the process of looking for a Golden retriever puppy  We're contacting breeders of Goldens and I have an extensive list of questions to ask: OFA hip, CERF eye and SAS heart examinations, temperaments, etc. etc.  We're willing to wait and willing to pay well for a good puppy with a great family history.
Here is my question: yesterday I was talking to a good friend of mine.  He and his wife too, are looking for a puppy to add to their home.  (They're looking for a Lab.)  I mentioned that we're looking at purebreds because of the assurity of a good family history.  He told me that they have heard otherwise - that purebreds have the most problems.  He has been advised by several people that a Lab mix (or in my case a Golden mix) is not only the cheaper option, but (most importantly) the best as far as temperament and health.
Can you tell me what the best option is?
What is most important to me is that we will purchase a healthy dog with a great temperament.
Thanks SO MUCH for your time!
-Jason

Answer
There is a concept in genetics called "hybrid vigor." This means that cross breeding makes the organism stronger.  In purebred dogs, there are many genetic problems that crop up because their genetic makeup is so similar. Goldens are so prone to hip dysplasia, skin allergies, and low thyroid hormones because of this purity.

As far as temprement, that is dependent on the dog and its environment.  A Golden in a quiet house will have a wonderful disposition, while a Jack Russell Terrier in a house full of rowdy kids will be untrainable.