We stayed for 5 days while on vacation in Montréal.
Pros: It's a perfect location, extremely well-connected to public transport (lots of buses right by the apartment building and a metro stop not far away). Also has a nice view onto the famous Notre Dame des Neiges Cemetery and you are just a few minutes' walk from Mont Royal park, perfect for an early-morning walk/run. The apartment was just as in the pictures and very clean. The kitchen is well-stocked (pots, pans, dishes, etc.) so you can easily cook your meals if you wish! The bed and couch were comfortable and the AirCon worked well.
Cons: the next-door neighbor smokes at seemingly all hours of the day and often with the door open, so there was sometimes a cigarette odor which drafted into the apartment. Not a huge deal, but if cigarette smells bother you a lot, it's probably something to note. Otherwise, the apartment's a bit dark as there's no light toward the entrance/bed area.
Overall, it's a great place to stay as it's a very comfortable studio apartment and couldn't have a better location! Kim was also very responsive via text and phone which we appreciated.