My partner and I stayed at the Westin Montreal for one night while we were visiting Montreal, and overall, it is a nice hotel in a good location.
There's a convenient loading and unloading area when you arrive that is seemingly within the building, so it's shield you from a lot of the snow. We opted to park in the street, which was readily available during the weekend, instead of parking inside for a much higher fee.
We booked a cheap room online, and since we used the SPG app, we got Wi-Fi for free. Our room was relatively large, with the bathroom being very large. They gave us an option of a city view or an Old Montreal view, but they recommended the city view. The view was quaint, and much better overall view than the Hilton Bonaventure which we stayed up earlier in the week.
The staff here was friendly throughout, and even though this is obviously a convention hotel, I felt it wasn't just sterile like most of those convention hotels.
Overall, of the big branded hotels in the city, the Westin Montreal is a good option and very close walking distance to all the dining spots.