Alex,

Lets put things in perspective. The original CO was not overly aggressive to humans - that came after the Soviet occupation of the Caucasus when the dogs were taken to Red Star Kennel and human aggression was bred into them so they could be used to guard the prisons and other military and industrial facilities. A good CO is supposed to attack and intruder if the "stranger"is deemed dangerous.  There are some lines and some breeders who produce dogs that are not confident and they will backaway or run away from someone but continue to bark. That is not desired.

The dogs are supposed to protect whether the owner is present or not.  If it does not - keep it as a pet but don't trust your safety with it.. I know you don't .. :) this is for others.