The flat is very well located, close to the Nashmarkt and 10 minutes walking from the opera, in a nice neighbourhood. The flat is beautifully decorated, the kitchen and bathroom are as expected, and super clean. I was welcomed by Michi when I arrived from the airport - he was very friendly, and checking in/out couldn't have been easier.
I strongly recommend this place as a great base to visit Vienna. It couldn't have been better!