Great location - close to the Metro which was just a few stops to the central area and Vatican, and walking distance from the Colosseum. There are some nice restaurants and the famous Gelateria Fassi nearby. The area (especially towards Termini station) feels a bit dodgy at night, but it's fine if you're in a group.
The apartment is on the ground floor so you can occasionally hear a bit of noise from people on the street but it didn't bother us at all. Paolo was a great host - very responsive to any questions we had. Thanks!