Absolute B&B is a very nice place, but inconsistent service keeps me from recommending it.
First the good. The B&B itself is very nice -- the rooms are very spacious and clean, with nice furnishings. There's a kitchen (which guests can use) and a front parlor area where guests can read or hang out, which is nice -- an added plus compared to the other B&Bs we stayed at in Italy. The breakfast -- coffee/tea, juice, bread, cheese, jam, pastries, etc. -- was pretty good as Italian breakfast standards go.
The location is very convenient -- the hotel is about two blocks away from a subway stop (Vittorio Emanuele), which connects to many of the major sites in town (Vatican, Spanish Steps, Trevi Fountain, etc.); that subway stop is only one stop away from the central train/subway station (Stazione Termini), so it's fairly easy to get in/out of town; it's within walking distance (about 20-minutes) to the Colosseum/Forum; and there's a great gelato place across the street and a supermarket a half-block away. The immediate area is fairly lifeless, though -- seemed perfectly safe, but not much pizzazz, and very few restaurants to choose from in that immediate area.
What keeps me from recommending Absolute B&B, however, was the inconsistent service. There's no one who actually lives/works at the B&B full-time, so you inform the staff in advance what time you plan to arrive, and then one of them meets you at the B&B to let you in, give you a set of keys, etc. When we arrived, it was no problem -- there was someone there to let us in (even though we were about 45 minutes later than expected), give us keys, provide us with a map and directions, room was ready early, etc. Once we had our set of keys, it was easy to let ourselves in/out for the rest of our stay. We noticed, however, that with at least two other sets of guests (over only a three day period), the staff failed to show up on time to let the guests in, and as a result the guests were stuck waiting in the courtyard outside the hotel for about a half-hour each time. If my wife had not had an international cell phone which we let the guests borrow to call the hotel owner (we had already turned in our keys on the second such occasion so couldn't just let them into the hotel), they likely would have been stranded for longer. On another occasion, the staff did not arrive to fix breakfast; when we called them, they told us where we could find everything in the kitchen and we were able to put it all together in only 5 minutes, no problem, but again we would have been somewhat stranded if we hadn't had the cell phone.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC