I would highly recommend this flat and the host. It was an ideal location for me during a long-term stay for an internship. Close to the U1 line and other bus routes, I was always a short trip away from the city center. Cheap shopping options are numerous and nearby. The neighbourhood was safe and even as a native-English speaker I always felt at ease (can also say this for most/all of Vienna!).
Vera and Tom were immediately attentive to any maintenance issues that came up in the flat and were even kind enough to help me out with moving in activities. The flat contained everything I needed for a long-term stay and the kitchen is well-equipped to cook your own meals and host dinners, etc. Overall, I felt very comfortable living here.