In Vancouver fortunately most breeds are received well here. I know West Vancouver used to have some weird breed specific laws to it, but idk if they still do. The rest of Vancouver is quite accepting though, you can see pitbulls, american bulldogs, and all sorts of mastiffs out on walks regularly.
Also, have you guys heard of this breed before? It's one of my favourites (based on appearance).
The mighty Caucasian Shepard.
Definitely not a dog for an owner who has never owned a serious mastiff-type breed before. These dogs fall into the 'Livestock Guardian Dog (LGD)' category. This means they were meant to live with a herd of animals and protect it from potential robbers or predators. This is part of the reason these dogs can weigh up to 200 pounds (males are about 140-180 on average). They have a low prey drive (they don't chase much, little interest in that), but have extremely high defensive drives. They are loyal to their pack and their herd, anything else is a potential threat.
They are a very primitive dog, not many breeders at all here in North America, so poor breeding hasn't been too big of an issue yet. There's a National Geographic on it but it's quite biased against the breed, making them seem like wild super dogs capable of swallowing a bear whole. The reality is they are a dog and while their protective instincts are extremely strong (meaning you will always need to take care...you kind of have to with a 180 pound dog), proper socialization will help to teach with the difference between a threat and someone walking down the street. I've heard they can make really good family dogs. With the family they are extremely gentle and delicate.
This honestly is why dogs are my favourite animals. It's amazing what purposes they were bred for over the years and how that shapes their personalities.