Good book selection but overpriced clothes.
I'll be the first to admit it. I'm a bit of a thrift store snob. It pains me to pay full price for anything and I will find a way to get what I want for less. I shop around and know what things should cost and thus I know when things are overpriced.
I would say that St. Vinnies on Willy is good for cheap books but they overprice their clothes. Crazy you say? Overpriced at a thrift store? Well, yes. Yes it is. You can easily pay almost $10 for a shirt at St. Vinnies when the same shirt is $3.99 at Goodwill.
For this reason I basically avoid their clothes section and only look at their books and furniture. If I wanted to pay full price I would buy it new. So keep your $20 hipster "vintage" dress and I'll get four for the same price at Goodwill.
If you want to go on a thrifting adventure head over to St. Vinnies "Dig n' Save" on Park St. It is where all of the unsold goods from the regular surrounding St. Vinnies go to. You can find some really great stuff there sometimes because what was previously overpriced and not sold because of that is now dirt cheap.
You dig dig dig through huge boxes and pay for clothes/misc. items by the pound. On many occasions I have seen children sitting inside the boxes and burrowing down to find clothes. Seems kinda crazy, because it is. You'll spend next to nothing, but just make sure to wash your hands after you get out.