Bernhard's apartment is like Vienna: modern but romantic. It is clean and functional, with lots of light and beautiful, spacious balcony overlooking the inner backyard. Even though it was February, weather was nice so we had our share of balcony-time, and I suppose it's even better during the summer period.
It's approximately 5 minutes walk from Westbahnhof railway station, which is a transportation hub very well connected to the airport (every 30 minutes direct bus, cost 8€) or to the city center (there are 2 underground lines connecting different parts of city).
It is also a walking distance (5min) from Mariahilfe strasse which is known as the shopping street in Vienna.
Overall, we can highly recommend Bernhard's apartment as a clean, nice, functional and well situated.