Skip the tourist trap at Swartz's, go across the street to Main Deli! No line, and full of locals.
I had the classic smoked meat sandwich. It was great, as was the 1/2 pitcher of beer.
I'd skip the fries next time, they're the typical soft and slightly soggy thick-cut potato-y fries that you're not sure why you're still eating... oh yeah, as a vessel for that big blob of ketchup?!
I didn't like that you have to pay a fee to share your meal. They know a sandwich is too large for the average girl to eat, so they charge $2 to split it with a friend. I don't know if this is normal in Montreal or not, but it's just bad service. Feel free to share my pitcher of beer, but touch my sandwich and you'll pay for it!