I spent a full month here. It's only a block from all of the action in the centro storico, but is also on a quiet side street, so you'll feel like you have your own oasis to escape to.
The apartment itself is great, with lovely spiral staircases and a comfortable couch to relax on in the evenings. Great windows into the courtyard are great for letting the air in. But for the really hot days in the summer, you'll have A/C! (hard to find in many homes in Naples).
The bed is very firm, just bear that in mind if you're someone who prefers a soft bed. The spirals staircases and not ideal for small kids or people without solid footing. The washing machine came in handy but took some close studying to figure out how to work it.
The kitchen had all of the basics you'd need. And the hosts were absolutely amazing, going above and beyond to help me when I needed it. Their notebook of instructions were very helpful and answered almost all of my questions! This was the best place to experience the heart of Naples. I will miss it very much.