Location cannot be overstated -- you can view the Pantheon from the living room! Central to all of the "must-see" sites, and the apartment is big enough to accommodate 6 people easily. Check-in was easy and stress-free. Maria was extremely quick to reply to all of my messages. The apartment is spotless and thoughtfully decorated with interesting artwork throughout -we really enjoyed looking at all of it!
As other reviewers noted, the wifi is pretty non-existent everywhere except the living room, and phone reception in the bedrooms was spotty at best. Also, make sure to bring your own shampoo/conditioner/body wash, etc. (I often find these already stocked in some air bnbs - this isn't one of them.)
Overall, the apartment was great, and we would definitely stay here again for the location alone!