Flavia's place is at a great location - accessible to the closest metro station and a close commute to major attractions (Trevi fountain, Spanish steps, Trastevere, Sistine Chapels etc.). The apartment is really clean, spacious with more than enough room for 6 pax.
However, we did have some issues with the hot water in the shower as the supply was really inconsistent - it tapers on and off very quickly which made it a bit of a hassle if you were trying to get ready quickly.
Also, as with most apartments in Italy, you will have to climb quite a few flights of stairs with your luggage in order to access the apartment. Overall, the apartment is great value.