My Wife and I had an excellent time visiting Miriam and Philipp in Vienna. They were very communicative and responsive.
We were given ale the needed information and on upon arrival we received a whole dossier on places to visit and where to go and what to eat in Vienna and in the vicinity of the apartment.
The apartment is just as promised- clean, functional and in a perfect location.
If we ever visit Vienna again we will sure get in touch with them and we recommend you do it.