Really not sure why it only has the one on Rue Saint-Hubert, but there is one on Rue Parc at the McGill ghetto, competing with Cafe Presse and Second Cup. The atmosphere here is the best out of the three cafes. Although it is plagued by "studious" students during the school year, El Mundo is a really good place to relax and do work on your computer during the summer.
I've tried their hot chocolate, which is amazing, not too sweet. It doesn't have the powdery taste that some cafes have in their hot chocolates. Now that it's summer, I've finally had the chance to try their iced teas (my favourite drink, if I may say). Try their green tea melon. It's refreshing in a hot summer day. A little pick me up in the gloomy Montreal weather.