Chris is a very caring and considerate host and responds quickly to messages. The apartment is spacious and comfortable and very bright and airy and gets a nice breeze with the windows open but some days the air-con is handy (I was there early summer and some unseasonably hot days). Location is great - trams and U-Bahn just a few minutes walk (tram 2 stops to Opera, U-Bahn 1 stop), nice supermarket just around the corner, lots of good restaurants and cafes in walking distance. I would stay there again if I get back to Vienna.