Amen to Texas' comment. We had a balcony room on the Explorer last year and loved it. We shared the room with some good friends of ours and alternated sleeping on the bed and the sofa. The sofa wasn't bad but very firm. I prefer a much softer matteress. But I believe you teenage son would be more comfortable on the sofa bed as compared to a pullman, he would have more room to stretch out. We were on the 10th deck in cabin #1670.
16 more days til our March 2nd cruise on Explorer