I would very much recommend degli Artisti! I stayed there with mrs. iapetus and the iapetus jrs. back in July 2016. We felt that the staff was very friendly. (They were particularly fond of the iapetus jrs., but this is Italy, so ... ) We would have enjoyed it even more if they had completed amenities such as the rooftop bar, which were still under construction back then and are presumably finished by now. The one issue with degli Artisti was pointed out by Perche:

mrs. iapetus didn't like this aspect of the hotel so much. The reasons behind this were that we were 1) pushing children in strollers up a hill at the end of the evening when we returned to the hotel and 2) it was a little farther from places near where we wanted to be (my favorite place to socialize in Rome is just west of Piazza Navona).

Otherwise, I think it's a great place, and I have recommended it to colleagues who are going to Rome this March. It's also conveniently located above the Barberini metro station, and there are stairs that take you up and down most of the elevation difference between the station and the hotel.