My parents had a lovely stay at Gianluca's apartment which was in a very good location, in the centre, close to restaurants, coffee places, public transport, taxis. Even though the place is central, off the main road, it wasn't loud at all in the evenings. The apartment was spacious well equipped with everything you needed. Gianluca even left the famous dessert called 'baba' in the fridge for my parents to try.
He was very helpful from the beginning towards the end, advising where to eat and drink, explaining the check in with pictures... I highly recommend that you stay at this apartment when you visit Naples! Gianluca is an amazing host.