Spent 3 nights here with our small children, and were very pleased with our choice. The communication with the hosts was excellent, and they were very helpful. We had a slight issue during our stay and they were quick to resolve.
The apartment itself is on the 4th floor of a building, but we got used to the stairs. There was plenty of room for the 4 of us, with 2 double rooms and a small but spacious kitchen/diner/living area. The living area window also had fantastic views of the sunrise over the top of the buildings. The location was perfect - in a quiet street off a busy area in the Trastevere... with plenty of restaurants and bars to choose from, even in the winter, and a very short walk to the tram stop.
Would definitely stay again!