Great apartment! Clean and spacious, The photos accurately represent the apartment- what you see is what you get, not trying to hide or conceal anything. The self check in process is a breeze, very straightforward. If you arrive late at night or expect to have communication issues (due to roaming etc) this could definitely make things easier. The apartment's location is ok, a bit off city center but still within a reasonable walking distance. Public transportation in Vienna is excellent and this makes the apartment's location less important in my opinion. The only thing worth mentioning in that aspect is we arrived late (around 8.30 pm) and had to walk quite a bit to find an open grocery shop.
The building and the apartment are very quiet, it is situated on the 2nd floor and yet you can hear nothing from the street below.
Bottom line- would definitely recommend this to a friend.