We stayed at Michael's apartment for three days while visiting Vienna. Overall, it was a good stay. The location was better than expected - only a 5 min walk to a metro station and less than 10 to a major train station (we were able to initially travel into Praterstern, the major station and it was an easy walk from there to the apartment). There's lots of space and it was convenient having a washing machine and drying rack to do a load of laundry. The only downsides to our stay were that the wifi would occasionally stop working (despite the router being located in the apartment) and it did get very warm in the apartment during the day (even with keeping the windows closed and the fan on, as suggested) - at night it was a bit better, but you may still need the fan right on you to stay cool. If in Vienna again, we would stay again!