This apartment is amazing, it has everything you'll need and is in a very quiet, safe location! Good link by bus (number 13a) from the station which literally drops you at the apartment. A very good supermarket is about 50 m away which is handy for getting all of your essentials. I would recommend sampling the atmosphere at Cafe Central (you can reserve a table in the UK) and book it after 15.30 in the afternoon (not on Tuesdays) when the pianist is playing. The cakes are out of this world and not too pricey (5.2 euros). It is so easy to walk into the centre of Vienna from the apartment. If you want to go to the Prater amusement park and Schonbrunn Palace you may need to get a 24 hour Vienna pass which costs 8 euros.
I would not hesitate to recommend Claudia's apartment