The appartment is really nice, in a quiet area, but very close to the busier city centre (just 4 or 5 tram stops). The beds are very comfortable and the building has a lift, which makes it easy to access with luggage.
Line 1 stops almost in front of the main door and the supermarket is just across the street. The photos (website) are real, the appartment is clean and spacious. We stayed with a family of 4 adults, and enjoyed our citytrip to Vienna even more due to this perfect accommodation.