The good: the apartment is functional and well-located if you want to hike Etna and stay in a quiet place. The town of Nicolosi is lovely and there are great options for food in walking distance. The apartment has a yard with two cute cats, and there is parking on premises. Rosario and his wife are lovely hosts, responsive and very polite.
The not-so-good: we thought a few things could be improved. The apartment was not very clean, particularly the shower curtain was quite dirty. The layout of the apartment is not ideal (it was fine for the two of us, but if you are more than two people, there is not a lot of privacy), and the a/c did not reach the bedroom. My husband had to sleep on the couch directly under the a/c unit to feel some cool air. Finally, there are no windows that can be easily opened, and unless you leave the main door open there isn't much light or air circulation.