I visited Montreal for the first time and the end of September 2013 and rode the city's subways. It was only a long weekend, but the experience was pretty good - particularly during the weekdays. The trains ran pretty quickly. And as a New Yorker, I thought the subway is pretty easy to navigate. I also like the multiple far options that the system provided - single fares, 2 ride tickets, 1 day passes, week passes, etc. If you want to save some $$$ while on vacation, the public transit in Montreal is definitely worth the try.