My partner and I stayed at the Residenza del Duca for 5 nights at the end of December 2010, taking in the New Year celebrations in Amalfi.
The hotel is conveniently situated in the centre of this very charming town, just a short walk from the bus terminus by the harbour. It comprises the top floor of an old residential building; our room looked out over a small square with a glimpse of the sea beyond. Above all, it was very quiet, aside from the church bells ringing from early morning. There is no lift access and thus various flights of stairs to negotiate so I would not advise the hotel for those who may struggle with steps.
The hotel is very charming and the owners could not be more helpful. A good breakfast is served. Accommodation could not be faulted; comfortable beds, traditional furniture, tea/coffee-making facilities, a very good shower-room with effective shower, everywhere impeccably clean.
There are many restaurants in close proximity and all recommendations given to us by the hotel were very good.
I feel that the Residenza del Duca offers very good value for money and is an excellent choice for visitors wishing to explore the Amalfi coast. I would also add that the local bus network is very good and reasonable in price so a car is not necessary for exploring the towns along the coast (and parking a car is a challenge around here).