The sliding bunk is 45"w/71"l and factory foam is about 5" thick. I've replaced mine with 8" thick memory foam so no more bottoming out.
The dinette bunk is 39"w/74"l and about 3" thick. I find that back sleeping is better on the dinette bunk due to the increased length and side sleeping is better on the sliding bunk due to the thickness. YMMV, though.
