GREAT location. Quiet, calm area with only 10-15 minutes to Circo Massimo (Collosseum, Forum Romanum etc) with the bus.
Make sure to also have time for renting a bike and go up the ancient road of Via Appia Antica - very close to the apartment!
Marzias friends/relatives met up at the apartment and even though We checked in after midnight they were very helpful - tipping us about buses, restaurants, sites and so on.
Easy checkout as well!