Antonio's place was simply amazing. I came in a group of 4 friends and stayed for two nights. The apartment appears to be relatively new, has a modern finish, and is very clean. The patio/balcony area is huge and I only wish I had spent more time there.
Antonio was very kind to meet us in person and show us around the place; he was also very generous in providing us with bread and a stocked fridge that was all on him - wine, milk, water, juice etc.
The location of the apartment itself is not far from the central station, about a ten minute walk. However if you have heavy luggages, the roughly paved streets of Naples will make your journey seem longer than it actually is (compared to other Italian cities). Antonio's place is on the 5th floor, and there is no elevator. He's happy to help you with your bags though.
Otherwise, this place was a rare gem in my opinion and I wouldn't hesitate to stay here again.