This is a VERY convenient location, one block from the metro and near several good restaurants. It is a busy street but not at all touristy. The center of the ruins (colosseum, etc) is an easy mile walk. The apartment is outfitted with everything you will need and Danielle is very helpful (he even got us a reservation at a restaurant!) Ostiense, Testaccio and Trastevere are all lovely neighborhoods with lots of local food and fun.
The apartment is spotless and equipped with hair dryer, washer, dishwasher, etc. Our group of 4 had plenty of storage and room to spread out. It's a great place to stay!