Hi, Harlan!
As a part of Disney's Summer to Remember, I had the opportunity to find the answer to that very question. Like you, I wanted to find out if the pull-out beds would be adequate for adults.
The bed in the master bedroom is really nice. It's springy, but firm, leading me to believe that one won't wake up too stiff nor all "bent out of shape".
The pull-out bed is great for children, teens, and young adults. It's a double, first of all, so it is a size smaller than the queen in the master bedroom. And it is not a traditional mattress by feel; it's more like a single block of soft, durable foam. This bed by no means unpleasant; I can see children and young adults managing quite comfortably on this bed. However, as backs and legs demand more support at night, the more traditional mattress is likely going to be a safer bet.
Have a wonderful stay - the new
Disney's Art of Animation Resort is fantastic!
See you later, celebrator,
-Deborah B.