We stayed one week at Al Seminario and loved it. The view is clearly one of the best you can imagine : almost 180° over lush rolling hills, the sea and the city of Viareggio in the distance (we could actually see planes landing at night), and even the city of Lucca in a corner. The swimming pool is amazing and the garden is full of surprises.
Simona at Salogi was extremely helpful in handling the reservation process and the owner was very nice with us.
the only downside is that the house lacks some modern facilities (the kitchen in particular is poorly equipped) and many doors leading outside are permanently locked.
I read some reviews about the road leading to the house, but it is not that bad unless you want to drive a Ferrari (which you won't). The location is very secluded though, so you'll have to take the car everytime you need to go shopping. However Lucca is only 20 mn away, which is quite convenient.