Mario's appartement was really clean, well decorated and really convenient for a 4 days trip in the city.
The neighbourhood is really lively, there is a tramway and a subway around 5/10 minutes walk (you're really close to the city center and tickets are so cheap in Wien!)
The appartement can be warm in the summer and some little things are missing (a broom, a frying pan) but nothing bad really. We highly recommend this place for enjoying Wien, it's a good value for money!