Silvia's apartment is ideally located, within walking distance of all sights and some great bars and restaurants close by. It was very hot while we were there and we found it difficult to cool down in the apartment. Communication with Silvia was great and she kindly left the keys for us at a local bar as we didn't arrive until really late.
The fabulous location does mean that it was quite noisy until late at night and again early in the morning with delivery lorries etc but it was worth it to be so close to the Duomo.