Be sure to make reservations otherwise you'll be sadly disappointed that they're book solid. I've been to Montreal twice and both times made sure I booked in advance.
During the warmer seasons they open the restaurant windows so try to snag a seat there as it's the best seat in the house or venture further back into the restaurant for a more intimate setting.
This is hands down the best Portuguese food I've ever had. Their cod and risotto is to die for.