I agree that the old part is kinda neat - although a little bit "hey tourists - come here and throw money away - come on!"
I used to go every year when I was in college. we would race at McGill - some park thing on a hill on their campus. The best part was at the top of the hill were some stoners that would be hanging out in the park, so you would run by them and be sucking air and there they are breathing pot into your face... which is nice.
I never ran well in Montreal - but I did get drunk a lot - thank goodness that they water their drinks down or I'd have died the first year or two.