This place is the most bare-bones, to the point bakery in the world. Don't expect some sort of trendy looking place selling overpriced baked goods. You're here for the bagels, and if you're stuck needing bagel accessories, they have those too.
If you're not familiar with Montreal-style bagels, they're not what most people are used to. Most people are familiar with the New York style. Montreal-style bagels are smaller with crispy and sweet crust and a lighter overall texture. They're simply phenomenal with a nice schmeer of cream cheese, and don't even need toasting in any form to be excellent.
They're sold at a few locations around Montreal (I bought more at the Marche Jean-Talon before leaving town) but getting them right out of the massive wood fired oven at the source on St-Viateur is so much better.