We had a great time in Luisa&Klaus's apartment with our 3 sons for 2 weeks. Communication was easy and they were very flexible. The flat is spacious, sunny and calm, you can not hear the traffic on the top floor. We were lucky and we could use the roof terrace in October. The terrace has access from the flat which is not obvious from the photos.
The neighbourhood is very nice and lively and not touristic at all. The first district is only 20 minutes walk even less by public transportation. We also really enjoyed the closeness of the huge Augarten!