The best part for us was the heat, since, when we visited Vienna, it was cold. The apartment was clean enough. Also in a convenient neighborhood to use the tram and underground to go around. The decoration and all rooms are lovely.
The only thing needed is a pedal bin for the bathroom. If you sit in the living room it could be noisy from the apartment above, but we didn't use it much, so it wasn't a big deal. In the end we had a great time at Nedjelika's :)