Thanks Ruby, they are absolutely lovely in temperament. I'm going to copy and paste something I wrote earlier to give you an idea of what they're like - I can't write anymore right now - am wrecked from all the puppy-sitting!
"Like with most dogs bred for aggression-related work (shepherds use them in the hills to protect their flocks from leopards), I think each dog's temperament depends on the upbringing of the dog - ours are all affectionate because from the word go (and we got them when they were WAY too young to be taken from their mothers, we were feeding them every two hours from a syringe type thing!) we handled them a lot, took their food away and returned it etc, so now the family members can do ANYTHING with the dogs and they don't even growl. On the flip side I've known Bhutia owners who have kept their dogs chained up and hardly given them affection, and as a result those dogs are completely vicious. Sad but true. I think the same can be said of other breeds like German Shepherds, Dobermanns, Rottweilers (ESPECIALLY rotts - my blood boils when I read some of the bad rap they get simply because of bad upbringing.) "