Fantastic location less than 1 mile from the main sites with a bus stop 50 feet from the front door. Easy walk to grocery stores and some good restaurants. Apartment was well equipped and very comfortable for our 5 day visit. Our only issue (and pretty minor) was that the room with the toilet was quite small. I'm 6' 1" and 220 and it was a tight fit :-) The bathroom itself (sink, shower and bathtub) is spacious.
Diana was a great host, was easy to communicate with and if we came back to Vienna we would be happy to stay here again.