We stayed for 4 days, and the apartment was very comfortable and with heat lighting. Very close to the metro station which also, gets you directly to downtown of Vienna in 10 minutes.
Our overall experience was great, the apartment is perfect for a family - I went with my parents and my girlfriend.
The only negative thing I would say about it, is that I missed having essential ingredients for cooking such as salt / sugar / oil. As we stayed for 4 days, buying a bottle of oil or sugar /salt was too much for a few days but, still; besides that, everything was perfect.