IMO, there's not much of a difference if you are placed in Acadian House or Magnolia Terrace in the mansion section. These are both the buildings that do not house Royal Rooms so if you book any category other than preferred and Royal Rooms, and you request the mansions, you will be in one of these two buildings if they accommodate your request. To get to the mansions, you have to walk the long way around the pool and over a bridge. To get to the preferred rooms in AB, you walk straight past the pool and they are right there. Not a huge difference for the price, IMO.