Booked through hostelworld.com.
The location was fantastic - a five minute walk from the main attractions and downtown Vienna. Much closer than most hostels, which are located near the main train station.
However - its attractions end there! This hostel is super sketchy. We had difficulty communicating with the woman in charge of check-in (she would be the receptionist, if there was a front desk) as she barely spoke English and it took a while to make her understand that we'd already reserved a room. The room was unfinished, which holes in the walls, and a back door that looked off into a courtyard full of junk. Upon further investigation, the back door came off its hinges. The bathroom was miniscule, and the sink not securely in place. There was no hot water the first night - it appeared our proprietress had "forgot" to turn it on. The third night we stayed in a 12-bed dormitory-style room, which was located through a couple doors behind the bar in a creepy illegal-immigrant-hiding-in-a-back-room sort of way. The room was far too small for twelve beds and had no amenities whatsoever.
I would NOT reccomend this hostel to anyone, despite its great location. That said, we had no real problems while staying there, other than a general feeling of uneasy creeped-out-ness.