I was in Rio for one month last June. Here are my suggestions:
Sheraton: A beautiful property, excellent guest service and medium upgrade opportunity. The rooms are decent, well maintained and the lobby is spotless. The only problem is the not so ideal location. They do offer a free shuttle bus, but even that is a headache. Waiting in the scorching sun for the bus is no fun either.
However the views are stunning. Beautiful, picture perfect panaromic views of Sugar Loaf and Copacabana/Ipanema Beaches. A feat that no other hotel can meet.
One of my good friends stayed at the Copacabana Palace, as a Platinum Card FHR. Absolutely dreadful experience. Besides the poor quality rooms, unexceptional guest service and iffy location; we were treated very poorly. The hotel has a strict policy, they didn't permit me to go up to his room!! We even spoke with the manager and he insisted for the security of guests they do not allow this. Even after we offered to register my name. It was 2PM in the afternoon, my friend was so upset, that we both just went to the room. To my surprise security actually chased us and threatened to call the police! If I didn't "get out" of the hotel. What a nightmare!
I have never not been allowed to bring a guest to my room ever. In some cases, they request for me to register the individual. Typically without much fanfare. Copacabana was very rude and not accomodating.
On a brighter note, I have heard good things about the JW Marriott. I don't know from personal experience, but I encourage you to check out the Marriott forum.
[This message has been edited by MaisonUnitas (edited 01-07-2003).]