Oh McKibbins. I have been coming here since I've been old enough to get into bars. It is quite popular with the McGill and Concordia crowd but despite that it doesn't have the feel of a student bar. You'll often find people of different ages enjoying a drink here. The bar is spread out over three floors. The first two floors are more of a pub while the third one has a dance floor and is a hybrid of a club and a pub. There is live music on weekends and in general the vibe here is pretty good.
Being an Irish pub you can expect typical bar food like fish and chips and burgers. In general the food is pretty good here and consistent. Last time I came I had a burger which was pretty enjoyable. If you're feeling brave (or crazy depending on how you look at it) you can take their Reaper Wings challenge which involves consuming 12 super spicy (think thermonuclear level of spice). If you succeed you get a t-shirt and your name on the Wall of Fame. Tread lightly though because the spice level is very intense.
If you're looking for a casual and laid back night out then McKibbin's is the place to come for that. It has good food, reasonable prices and overall the experience here is pretty enjoyable. I have been here many times and always enjoy myself when I come.