My wife, my 11 years old son and me have satisfactorily been staying in Wien in the Christoph's flat from 29th June to 6th July 2013 without any significative inconvenience despite being in a foreign country.
On the contrary, the flat is just as described, really well dimensioned , the large terrace is a plus, and fully-equipped but the microwave. It is located in a perfect area near the historical centre, which also enabled us to economize on transport charges. In fact, for 3 out of the 6 days of our holiday in Wien, we went around the city on foot only. Christoph has been kind and forthcoming, just like ALL the viennese we have been speaking with in the parks, shops and on the street when asking them various information.
Therefore, I would definitely advise you to consider the Chirstoph's flat as your first choice in your Wien stay . Should you need any further clarification, feel free to enquire me. I will be delighted to answer.