We visited Naples with the intention of seeing Pompeii and this was a great place to stay for that. The apartment was very clean and it was an easy walk to the archaeological museum as well as lots of great restaurants (including La Michele from Eat, Pray, Love). It was also within easy walking distance of the train station to catch the Circumvesuviana. The view from the balcony of the city with Vesuvius in the background was absolutely beautiful, especially at sunrise, and it was fun to stand outside and listen to a festival on one of the nights that we were there.
When we first arrived in Naples, we got a little lost walking from the train station to the apartment, but Umberto and his girlfriend were kind enough to wait around for us and check in on where we were. They met us at the apartment and showed us around, and both were very friendly. Overall, I would definitely recommend Umberto's place if you're going to be in Naples.