Great base for which to explore Rome! Modern, clean and about 10 minutes walk from Valle Aurelia Metro. There's also a bus that goes from outside the flat to the city centre in about 25mins.
The only downside I found was that the apartment is by the main exit to the block. So if you're a light sleeper you might get woken up by people going to work in the morning.
Overall Arianna and Marco were great hosts and I would definitely recommend the property.