Actually I am curious as to why you chose to focus on Cananda and Austrailia. Personally, and I know I said this before but it bears repeating, I think you need to figure out what kind of place you want to live before picking a school. I really think place is a far more important factor, you could be at the greatest school in the world and then just completely hate the weather. Montreal is a lot different from Calgary or Sydney or Perth or Austin. And I think that is really the most important thing.
And not to sound like a jingoistic flag-waver... but by keeping the US an option, you really have choice of hundreds, if not thousands of schools... that maybe the exact one you are looking for.
Stop drop and roll will not save you in hell. --- seen on a church marque in rural Virginia