This is an amazing apartment. The lounge is absolutely huge! The location could not be better, on a quiet street leading off Stephansplatz. It is only a couple of minutes walk to Stephansdom so therefore about as central as it gets! We stayed for a long weekend and it was so quiet, not a sound from outside. It's an old building and some of the fixtures and fittings are not the most modern but in no way does that detract from the overall experience. No hesitation in recommending Victoria's apartment, it would certainly be our go-to place for future trips to Vienna.
One little tip, if your looking for good left luggage options, the left luggage lockers at Wien Mitte Landstrasse station are cheap, safe and secure and of course at the station you catch the train to the Airport from!