I went to Montreal's Comiccon in July 2016 which took place at the Palais des Congres de Montreal. I thought that the Palais des Congres was a good place for the event for a few reasons; it is large and it is connected to the underground city and directly connected to Place d'Armes Metro station which means in case of bad weather, you don't have to go outside in order to take the metro.
For the amount of people in the Palais des Congres for Comiccon, I found that the temperature could have been cooler as I was sweating mildly while walking around Comiccon. I've eaten at two of the places at the food court (Tim Horton's & Subway). Another thing I like about Palais des Congres is that it is within walking distance of Chinatown which means good Chinese food.
There is free wireless within certain areas of the Palais des Congres (mainly on the same level as where the food court area is). However, the free WiFi does not extend throughout the entire complex.
The place is well maintained and very clean.
I rank Palais des Congres de Montreal as a 3.5 stars which like my other reviews, I've rounded it up to 4 stars. I've been to the convention center in Las Vegas and the Palais des Congres is on par with the one that I've been to in Las Vegas.