The apartment is very well located. We walked in all directions on different days, including to the Vatican. The area is made up of very quaint, mainly pedestrian back streets with lots of character. There's something interesting round every corner.
Inside the apartment, the decor is acceptable, the beds comfortable and generally it's all good. There's not much natural light in the main room but you don't go to Rome to stay indoors anyway.
The arrangments were very clear, check-in was simple and communications were excellent.