We stayed here when we visited Rome on a 5 day city break in February. The guesthouse itself is clean, quiet and the staff are extremely welcoming and friendly. The breakfast was served on a tray, to your room, every morning at a time you chose and you were able to choose from a variety of breakfast foods and juices.
The bathroom was lovely, the room was cleaned regularly and the wifi was sufficient. The room itself is decorated nicely.
We expected to have to get the metro to see the sights we wanted, as on a map the guesthouse looks far away, however it was around a 30 minute walk to the furthest part of Rome. As the weather was so lovely, we didn't mind the walk.
The only con is that we required an iron, which they did have but it was rubbish, and they did not have an ironing board. Aside from this minuscule factor, the guesthouse is lovely and we will definitley be returning.