Mention hot sandwiches and Momesso's immediately comes to most of our minds... but Momesso's is just the tip of the iceberg. It is fact that Momesso's serves up an excellent Sausage sub and some cold beer, but have you ever considered venturing to Lasalle or other burbs?
For those who rarely venture to the south west regions of the island Lasalle is a mostly residential suburb that has a few hidden gems worth trying. One place that make an excellent belly bomb is Manzo Pizzeria located at 1033, 90E ave. corner Boul Newman. Manzo got smart and instead of buying lousy quality sub rolls, uses their Pizza dough to bake fresh rolls to order for their subs. Damn these things are good. But make sure to take a good dose of Zocor before going.
Lasalle Drive-in, makes a sandwich called Pete's special, Like Manzo they make their rolls from the pizza dough. Different from Manzo in a number of ways, the Pete's special is good but I perfer the fact that Manzo piles on shredded lettuce tomatoes.
Although not a sandwich joint, of notable mention is Campagnolo located at 1714, ave. Dollard corner Réjane in Lasalle is a BYOW that describes itself as serving fine Italian cuisine. The food is excellent, and is traditional trattoria type fare. Although the dining room does not qualify as what one might classify as a fine dining, it is relaxed and unpretentious, and a good place to sit down to a decent meal with the family.
On the other corner of the island is Cafe Milano at 5190 rue Jarry Est Saint-Léonard, (514) 852-9452 makes excellent Italian sausage subs and other hot sandwiches, in a similar style to Momesso's. Perhaps not as heavy as Momesso's, but very good.