My husband and I stayed at the Navas for 3 nights and really enjoyed it after coming from a tiny Madrid hostel. The hotel is, as others have noted, a bit difficult to find - the taxi will drop you off near Navas, but there is another (much older) Hotel Navas on the corner of Navas Street. No matter -- we asked and got pointed in the right direction.
The hotel staff is very polite and helpful. I speak Spanish, but almost every staff member speaks fluent English if needed. The lobby, to the right as you enter, has a pay-per-use computer for your internet needs, and also has a wi-fi connection for those who bring their own computers. There are several brochures for tourist excursions available, and a bus schedule for the airport on the wall. We used the bus transportation to the airport when we left for just 3 euros - quite a deal compared with the taxi we came in on.
The room was incredibly spacious, and the bed was enormous and very comfortable. Bathroom was elegant, with a good, strong shower, hairdryer, and other amenities (soap, shoeshine, etc.). We also used the laundry service once, for a pair of pants, and they were returned washed and ironed later that day, which was a nice touch that we weren't expecting.
The neighborhood is very lively at night, and you will find a mix of tourists and local "granadinos" eating and drinking outside. It can get a bit loud at times, but it was by no means unbearable. The balcony doors and thick curtains and blinds kept a lot of the noise out. You are also within walking distance of Gran Via and other main boulevards. We also walked to the Albaicin and Sacromonte neighborhoods (hilly, but doable) from our hotel.
Hotel Navas provides breakfast in the morning (mine was included in the price of the room), which is a positive. You will find anything from pastries like croissants and "bolleria" to sausage, eggs and toast, to yogurt and fresh fruit and orange juice.
One slight annoyance was the rather antiquated policy of having to turn the key in at the desk every time we went out and then ring back in. However, no big deal. I would easily stay here again. A very comfortable room in a good location.