I had a great time and really enjoyed staying in the guestroom of Zuzana & Stefan. Everything was fine, the room, bathroom and kitchen were clean - nothing to complain about.
And they live in cool neighboorhood - there are some good restaurants and you get to the city centre or to the University in a few minutes by tube.
Unfortunately I didn't have much time to talk to my hosts as I was at University or exploring Vienna most of the time. But as far as I can tell there really friendly and helpful.