The apartment is in a great location, very close to Piazza del Popolo and many other attractions, restaurants, and shopping options. Despite that, it's very quiet in the apartment because it's just off of the main streets.
There is a good amount of space inside; the living room and kitchen are fairly small but there are three large bedrooms and two large bathrooms, one with a shower and one with a bathtub. The beds are big but not very high quality mattresses; the are very soft (which may or may not be good for you) but with some springs missing here or there so the firmness is inconsistent. The bathrooms are pretty nice but the doors do not close shut properly or have locks, so if privacy is a concern for you this may be an issue.
The check-in went smoothly for us but it was slightly stressful having to provide an exact time to meet up at the apartment. Fortunately for us our flight arrived on time and I was familiar with Rome already and could estimate when we would make it to the apartment, but I could imagine this being more stressful if things don't go to plan or you don't have a good internet connection when you arrive, as they messaged several times asking for an exact arrival time.
That being said, they were very friendly in person and provided us a list of restaurant recommendations in the area, and checked in with us the next day to make sure everything was OK.
I would recommend staying here, the location is really great and that's likely the most important feature for a trip to Rome.