It was a pleasure to stay at Alessandro's for a month (mid August to mid September). Alessandro is an open, communicative, helpful host.
You are staying in his flat, so he is basically your roommate, but he leaves you room to retreat.
The only thing that really bothered me was the noise - not the one of the people at Piazza de' Pitti, if one wants to live neat a Piazza you should expect there to be people. Rather the sound of the restaurants throwing away their glass bottles at any hour, also at night, and the garbage truck in the morning picking it up, crashing all the glass.
But all the other positive factors such as the beautiful location and the view from the room as well as Alessandros hospitality more than outweigh this single issue, in my opinion.