The apartment is fantastic, with stunning views through most windows, plenty of space to make yourself at home and everything you could possibly need during your stay.
The location is perfect. We found it very easy to get about (with a hire car) and did loads of interesting day trips including Florence, Lucca, Barga, Cinque Terre, San Pellegrino in Alpe and Grotta del Vento. There are also plenty of lovely walks to do within a 20 minute drive (we managed two and left our hiking map for future guests to use).
Carlo was extremely helpful, and he and Anna went out of their way to make sure that we were comfortable and had everything that we needed (including (high chair, travel cot etc).
I think it goes without saying that the local food was exquisite, but I'll mention it anyway. All of the restaurants that we tried were excellent quality, friendly and accommodating to my wife's gluten intolerance (something that we were worried about with all of the pasta and pizza!).
I would not hesitate to return or recommend to anyone interested in exploring this gorgeous part of Italy.