Ooh la la, I guess I'll have to try St Viateur. I've been bringing home dozens of Fairmount bagels for years (plain or sesame), and yes, they are far better than any in the US. Including New York.
One huge difference is that Montreal bagels (or at least Fairmount's) are hand-rolled and salt-free. They tend to be a lot smaller than the monolithic ones in the US, perfect for a snack.