Southern facing rooms 518,519 and 520 top floor from front to back. 418, 419 and 420 are below them and are also good in my opinion (better than the 4th floor delux ocean view rooms 401-404). I can't remember which ones had the adjoining option but we've never had a problem with noise from the adjoining option. A few that are often overlooked are 507,506 and 505 in that order. They are the top floor city side rooms that overlook the breakfast area. You'll hear the buffet getting set up in the AM but if you're up early anyway for breakfast who cares? Those rooms offer decent water views views out the side of the Casa to the south and the fact that they are under cover means no rain on the balconies. I will say if you don't like the room you get management is very accommodating in letting you move to another or your preferred room as soon as one or it is available. However, ya have to be willing to pack it all up again to make the move. We only did it once when we were stuck in delux ocean view room 401 that had a balcony that made you feel like you were in a closet... 501 opened up the next day and they moved us to that room (one of the 2 best in the hotel in my opinion being 501 & 504 if you're going to pay for delux ocean view).
What about the top floor facing east? Are any of those rooms worth looking at?