Actually not bad of a place, as it is with most thrift store, the variety and the availability is really changing. So you can get lucky or not.
If you are grossed out by places like "village des valeurs" and renaissances. It's a great place for you since all the good stuff is already skimmed out. In fact, there is a few stores like this one almost neighbouring each other so if you want the full experience. Look around on Saint-Laurent.
But to my taste it's a bit lacking this "thrifty feel"