I had a Chow mix with a personality that was 100% chow chow. Her name was Shiner and she is the reason I defend this breed so passionately. She was my heart dog, and I'd be lucky to ever have such a wonderful companion again.
The deal with Chow Chows:
Patience with strangers is not something they possess. They like to get to know someone before asking for physical contact. If someone comes up to a Chow Chow and pets them on the head, they're most likely going to be snapped at. It's intruding and threatening to almost any dog, and with their lack of patience, Chows will snap at that.
A lot of people say that they snap/bite unprovoked, but they really don't. Chows are VERY subtle in their body language. I've seen Chow Chows that do nothing more than widen their eyes or pull the corners of their mouth back before snapping. They are naturally very "stiff" looking dogs, so you can't tell if they are tensed and ready to snap unless you know them well.
Let's say a Chow Chow is standing outside it's yard and someone walks by. Any other breed would most likely bark, growl, and give a huge obvious warning before chasing the person. A chow will not, and at a distance the dog barely looks like they care about someone walking on their property. (And yes, most Chows DO NOT LIKE strangers on or near their property.)
Basically, the breed is "cold" to strangers and will not tolerate being treated carelessly. They're best owned by a dog-savvy person who doesn't want to control their dog's every move. Independence is the word with chows.
They are great dogs with their families, I couldn't have asked for a better friend and protector than Shiner, but if you want a social butterfly or a dog that will tolerate being man-handled by strangers, look elsewhere. They are NOT a dog for everyone.
</senseless rant>