We stayed for 10 days in this appartment and it was a great experience. Appartment has everything one could need - including dish washer,air conditioning and washing machine. For a long stay it was very imporant.
The place is located right next to St. Peter's Cathedral and there is a lot to see in the neighbourhood (in the walking distance you find Piazza Navona, Pantheon, Campo di Fiori and lots of restaurants). However getting to the center is a bit trickier if you only rely on public transport. The bus 64 is always full and metro is located in about 15 min walk. So still doable but a bit less convenient. There is also a train station nearby (5min walk) from where you can get to Termini or to the beach!
Michela and Leonardo are great hosts who provide you with tips and all the information you need. They are very responsive and our check in and out was also super easy. I definitely recommend this place!