The area is safe, not far from the city center but also really close to the Prater. There is also the subway behind the building. The appartement was great and there is (almost) everything you need. About the waterbed, my father liked it and my mother hated it; i slept on the couch and it was good for me (a bit hard but not a problem from my pov). Georgios was really nice and answered all my questions.