[rafjen]

Oh tough one- How much time will you spend in the room, if all 5 will just be there for sleeping I'd go on location HRH (looks fab but heard club room is far too small) or RPR (close to IOA and I've heard the club room is bigger). However if you will be in the room a lot I'd try Portifino. The queues for boats can get long at busy times. We always go on price as we spend most off out time out of the room.
We have done 5 adults in RPR it was tight but perfectly manageable and the fold out bed was comfy.