I'm an American who studied and lived in Montreal for 5 years and will take a Montreal bagel over a NY one any day. Don't get me wrong - I love NY bagels, but there's something about Montreal-style bagels that are just amazing. Anyway, I digress.
If you simply want to get a freshly made bagel to go, I would recommend going to any of the St. Viateur bagel factory shops instead. If you want to sit down and enjoy a delicious bagel sandwich with a side salad and maybe a cappuccino, then definitely come to this cafe instead. Do catch the attention of one of the servers first, and she/he will sit you. Make sure you have cash on hand, as this place only accepts cash now. There are a couple of banks nearby, so you can withdraw some beforehand.
Highly recommended stop when visiting Montreal.