Harry was a very welcoming host, showed me around the apartment and readily answered all remaining questions; check-in was uncomplicated and quick.
The apartment was just as described and was well represented by the photographs; I found a very clean an comfortable place to move into.
The area is very central, yet quiet, with plenty of good restaurants nearby (for authentic Viennese cuisine, Herlitschka is, literally, just across the street, and the brilliant Salm Bräu a short walk up the street). Public transportation (U4 Stadtpark) is about 3 minutes away, but most destinations within the city centre can easily be reached by walking as well.
Overall, it's been a very pleasant five days, and I would certainly put Harry's place on top of my list for a return visit.
Thanks again!