We have stayed at this bed and breakfast twice and really liked it both times. It is a perfect place to stay near St. Peter's, as the Vatican is practically right outside the door. We stayed in an apartment with our own kitchen and bought food (breakfast is provided for you to make yourself) at a nearby grocery store.
Compared with other hotels that have the same amenities in Rome, it is a very good deal.

The owner is very nice, lives nearby, and the daily cleaning is impeccable. I'd recommend asking for the 2nd floor apartment, since it overlooks a small courtyard and does not get much noise from the street.

A great base for exploring Rome.

A very central apartment (3 bedrooms) with a kitchenette for guests use, which was handy. Continental breakfast was self service, from the fridge, which was stocked with juices, yoghurts, bread etc. The location is great, very very close to St. Peters. It's quite a walk from the metro (15 mings) but bus no. 64 goes to Termini station from the end of the street. The apartment is nice, very clean rooms of a standard size for hotel rooms. The only downside was that it's at street level and if you leave your windows open overnight there is quite a bit of noise during the night. However all rooms have air conditioning so when we kept the windows closed the noise level was much reduced and we slept well. The owner was lovely, very helpful, and a lady comes to clean every morning.