Good place to stay and visit Vienna. It's connected via U-Bahn, Buses, and Trams to all points so that you can be in any location in Vienna in 20-30 minutes.
The apartment is clean, good for families, and has everything you need (wifi, fully equipped kitchen etc).
Maxi is also very nice and eager to help.
A small balcony would be nice.
I highly recommend this apartment.