I stayed at Pergiacomos apartment during a month and I couldn't have wished for a better place to stay. What makes this apartment unique is its location, as it lies in the somewhat hidden local community of Pizzofalcone, which manages to stay unique in its own whilst rubbing shoulders with BOTH the fancy Chiaia/Vomero, as well as the more stereotypical ("chaotical") Naples in The Spanish Quartiers a few minutes walk away. On top of that you have the charming St. Lucia and Lungomare (sea stroll) a stone's throw away. You basically have all the different flavors of the city a few minutes walk from your doorstep. Best and most convenient location for a full experience of Napoli.
Other than that the apartment is fully equipped with all the minor and larger things you need for a longer (or shorter stay). It's clean with a generous kitchen, great wifi, a washing mashine etc etc. Great care is taken for you to feel at home and Piergiacomo and Lucia are to quick respond time if you have questions or run into troubles.