Robert's apartment was beautiful, quiet, and had everything I needed for my last few days in Vienna. It was quite easy to get into the city center (the 1 goes straight to Karlsplatz, so it only took about 10 minutes). The only downside was the check in process - it would have been helpful to have more details than just to meet Robert at the apartment (he ended up not being there and his mother came to let me in) because I had no way to get in for about half an hour. I ended up just having to ring several doorbells until someone heard me. His mother Ida was very sweet and helpful and it all worked out.