My friends and I had a great two-day stay at Cristina's place. Her listing was close to public transportation and we had no problem getting to all the places we wanted to see. Our room was spacious with comfortable beds and a fan that helped cool the room (it was still a bit hot, but that's Rome in the summer for you). There were other groups of guests staying at the apartment in different rooms but we never had trouble finding available bathrooms etc.
Cristina was a kind and thoughtful host - she greeted us in-person during check-in, waiting for us when we arrived ~45 minutes later than planned due to a train delay. She was always around to answer questions or provide directions, and provided fairly-priced transportation to the airport for my early morning flight.