I cannot think of any better apartment for staying in Vienna.
It is very centrally located and yet very quiet. It is clean, nicely furnished, has very high ceilings and overall it is very "classy". Dina and her husband were very welcoming hosts, answering our messages very fast. When we arrived, a complimentary bottle of wine was awaiting us on the table.
The apartment has 2 bedrooms with double beds and a large living room with a kitchen. I am happy to recommend this apartment without any reservations.