your Caucasian Ovcharka is gorgeous - weight wise they seem to be about the same as my Neapolitan Mastiff but with the thick double fur of my Newfoundland.
I guess there aren't many of then here in the UK, although like the Tibetan Mastiff I'm sure they will quickly become popular.
Like with the Neapolitan you need to be a dominant person so that they know you are the pack leader.