The apartment was great, beds were comfy and the location was convenient - it's not in the centre of Vienna but the train station is very close and easily accessible. It was great for 5 girls interrailing and we really enjoyed our time there.
Our main problem was the ventilation - the rooms were 30C and the fans did not aid this, which was very uncomfortable so we could not wait to leave in the mornings. We would recommend this apartment as better in the winter months. The shower was very slow to drain which elongated showering times as you had to wait for the shower to drain. The bathroom also got very warm which was a problem for us changing in the bathroom but if you could do this in the bedroom then it would have been better.
Overall we had a great time in Andreas' apartment and would visit again. Thanks!