...make them suitable for the climate around here, hardy, mite resistant and winter well. Also many sites mention that they are quiet.
However, during my working with these hives, the other species he has were quite calm, most likely because of the weather being quite cool and we had little problem with them, the Russian strain however were quite active and the gentleman says that this is normal due to their being a colder climate bee,...
In my experience 42 year "cold climate bee" is nothing to do with agressive/ defensive behaviour.
Cold climate means that strain has sence to get ready for winter and keep calm in they hive during long winter. If they are "southern bees" they fly during winter, come out and feed brood.
Russian bee is "breeding product of USA", not real Russian.
You have also many other strains there, which have good over wintering abilities. Italian strains are plenty.
Many bees are aggressive when weather is bad. And when evening comes, some became really mad!
.Could this behavior be bred out with replacing the queen with a different one, or is it the case that this particular breed is overall more agressive despite what I have read and only seemed out of place due to the cool weather. ,...
Many hybrids are aggressive. Agression is bee's natural habit against enemy. Keep calm is unnatural habit, which has been generated through breeding.
I have not seen Russin bees however my summer cottage is 50 km from Russian border. In Finland we have real Russian strains, I heard, and they are not good.
I have had Northern race (mad), Caucasian from Canada (lazy), Krainian (swarming, calm) Italians and Buckfast and their every kind of hybrids.
Now I have 3 strains of Italians: 2 from Finland and 1 from Italy,
also I have 2 Elgons hives which clean mites away. One Elqon gived to me too much stings and I changed the queen.
I think that USA-Russian bee is "young product" and it is not ready yet.
"Some like daugters and some like mothers".