Dude, this place is awesome. It's HUGE and they have a ton of stuff...yes, even ON Halloween! Came here for some last-minute costume scrounging with my friends, and not only was the place completely packed, it was still very well-stocked. My friend easily procured a complete flapper costume with associated accouterments with plenty of options to spare, and this was after she turned down three variations of French maids and one Wonder Woman =P
It's true they don't offer returns on most of their items, but they do let you try on the costumes. Oh, and the ginormous T-rex coming out of their store-front wall is just awesome =D