We had a great stay for three nights. One evening when i wasnt raining we got to have a glass of prosecco on the terrace, and it was very romatic.
Before we dared to buy a 24h bus-ticket we walked everywhere. Two days in a row we walked to the dome and back, stopping here and there for a nice espresso or gelato. So it may take a while but the flat is within walking distance from the old town if you got good shoes.
The only little downside i can think of is that it wasnt very soundproof. You could hear people talking in the stairs and the noise coming from the elevator. But other than that everything was awesome!