I have clocked up a lot of nights here and have enjoyed everyone of them. The front desk staff are some of the best I have found anywhere in the world. To the point where I think they "carry" some of the other departments who are less efficient. Housekeeping is very poor. They fail to remove/change dirty glasses or replace missing laundry forms etc. i feel the room is never fully serviced during your stay.
The rooms are all very comfortable and I found it to be a "quiet hotel".
Bar - great, the Tapas style menu for the business traveller is excellent, allowing you to eat a little or a lot, depending how you feel. The wine goes without saying given the hotel has the best wine bar for miles around. Don't hesitate to ask the wait staff for advice, they are both knowledgable and friendly.
This is one of the best Westin's I know.