I live in NDG so Encore is like my friendly neighborhood record and book store. The selection of vinyl is quite good. They carry both new and used vinyl (as well as books, CDs, DVDs, and magazines). Their prices on bagged good / very good condition used albums is pretty good (ie: not over-priced) and they have a lot of albums in the dollar bins and also a large selection of $4.95 albums that are 3 for $10! I like digging through the discount bins and I like classic and progressive rock, 80's alternative, and ambient. I almost always find something fun on each visit.
Everyone who works there that I've met has been friendly and nice.
It's absolutely a great place if you live in NDG, and if you're from elsewhere in the city and are coming to this neighborhood, plan an extra hour and stop in at Encore - it's worth it.