I've stayed in the apartment with my girlfriend for 5 nights. It is situated 15 minutes by tram or tube from the centre in a quiet zone of Wien. There is also a supermarket within a 5-minute walk. The apartment has everything you need: dishes, a coffe machine provided with coffe, an oven, a fridge, and also a washing machine and an iron. It was very clean and the bed was comfortable. It was furnished in a modern and clean style.
Heidi was really kind and she always quickly answered at our questions. We would definitely recommend this apartment for your stay in Wien.