This has been, by far, our best experience in airbnb to date. First of all, the apartment: we had an amazing room all for ourselves, complete with a super comfy bed, a huge balcony and our own bathroom. Really, it was like staying in our own private apartment, with all the privacy we might need. And the apartment is super silent, I'm a light sleeper and found out that I slept better there than at home.
The location in Trastevere is great. This neighborhood is not filled to the brim with tourists like other parts of the historical center, so we could really feel the vibe if the city. Besides, it has great restaurants and for a much more accessible price than elsewhere. That said, I'm about fifteen minutes you're in the river, and from there all the main attractions are about 15/20 minutes way. If you're like me and enjoy walking (and Rome was definitely made for walking) this was no problem at all. However, if you want to catch a bus, there's a bus/tram stop about five minutes from the apartment. The Trastevere train station, from where you can get a train to the airport, is only a few stops away.
But enough about the apartment - what makes a place is it's people, and that was another high point of the experience. Flavio and his mother Giovanna (and also Mario) received us with a smile and open arms. They gave us tips on Rome and the neighborhood, and Flavio even pointed us to a special spot to see the New year's fireworks. We felt very welcomed by this lovely family, and if we ever come back to Rome we will definitively be back here.