Just spent 3 nights at the Centro Historico 3 weeks ago. The hotel is brand new (February 2003) and represent a very good quality for the money (I paid $120.00US).
Was upgraded to a (large) junior suite on the 21th floor. The view was quite impressive, the whole lenght of the room (about 25ft) was covered with floor to ceiling windows. The rooms located on the other side of the corridor seems to have only 1 small window. Bathroom is large and modern with a large glass shower and a separate tub.
Only good things to say about the hotel. Rooms are modern, the look is more "W" than a typical Sheraton. Restaurant serve good meal. No lounge but was offered breakfast coupons. They are still working on the top floors so maybe the future lounge will be located there. Also tried room service one night and it was very good.
The breakfast was a little odd because even if there was a buffet for breakfast I could not pick my-self what I needed. I had to ask the server each time and he had to go himself to the buffet...That was only reserved for those with coupons...Time consuming and a little frustrating.
I guess the W hotel is probably something else but if you consider the price of the rooms the Centro Historico represent a very good alternative.