On our first cruise, my sister stayed in 5009, the exact room on the opposite side of the ship. We were on 1 side of her and my parents on the other. We really liked being up that hallway as there isnt much traffic. Deck 5 is great because nothing is too far to go up or down to, you are right in the middle.
As for the beds, the couch will turn into one for 1 kid, and another bed will come down from the ceiling. We liked the set up of those sideways cat 11's.