I stayed at this flat with a large family group of 16. We ended up adding a 4th suite as the bed layout didn't work out. Cristiano and Valerio were very accommodating throughout the booking process. All messages were answered within 12 hours (there was an 8 hr time difference between us) and they arranged transport for the group from da Vinci airport and to Civitivecchia cruise port at very competitive rates. We came in 4 groups on different days and they met each group to explain the suites and give out keys.
The suites themselves worked out very well. All are within 20m and are up/down only 1 flight of stairs. The security is very good as we never felt uneasy at any time of the day or night. They were on a residential street with only a bit of traffic noise. The street is only 1 block long so only those needing to be there drove by. There are numerous restaurants nearby as well as a coffee, convenience and grocery store within 100m. All attractions we wanted to see were within about a 20 minute walk (Vatican City was about 45 minutes). There is public transit nearby, but we never used it as we didn't want to miss seeing a wonderful sight that was just around every corner.
The beds were comfortable and bedrooms fairly large. Kitchens all had full-sized fridges and gas stoves. One suite had a washer and another a washer/dryer. They worked well, but were quite slow (about 3-4 hr full cycle). There was plenty of hot water from the demand water heater, so multiple showers were not an issue.
This was my first AirBnB rental and was chosen after a long search (in part due to the large group size). We were quit pleasantly surprised with the suites, especially knowing how small some European flats can be. There were many favourable comments from other family members regarding this rental, especially for it's size and location. I would not hesitate at all to recommend this unit to family or friends staying in Rome. You will find Cristiano and Valerio very professional, friendly and easy to deal with!