This place is in a great location. It's close enough to all the transportation you could want. My wife and I literally walked to every site including the Vatican. It was about a 12 minute walk to the fountain, and a 45 minute walk to the Vatican. All the other sites were in between these two times.
As far as the apartment itself, it was great. This place is in the fourth floor, however, there is an elevator. The room and living space are very nice. The ceilings are very high and the decorations are tasteful. I would recommend this place to anyone visiting.
There was a small odor in the bathroom under the sink. It smelled of water damage possibly or possibly just a little musty. This was the only thing that was not amazing with this place.