Dario is a nice host, even though we didn't see him a lot as we usually got up early and stayed out late ;)
Room was as on the picture, really clean and basic. Breakfast was typical Italian (coffee, croissant, marmalade, I loved the cake every morning :)
Location is next to the city wall, so if the cab driver try to discuss with you to pay more than the airport fare as its outside of the wall, just let them drop you at San Giovanni and walk. Could have saved us 15 EUR.
For your exploring, there are a lot of buses around the corner, you can walk in 20 min to the Colosseum and to the metro you are in 10 min.
So all in all a good place to stay.