Here's a plug for the Escape-made bed extension for the 17B. We had Reace and the fellas make us one for our Escape when it was built in early 2012, but for some reason we didn't use it until our last trip in late September.
WOW. It made a HUGE difference in our comfort, and allowed us the guilty pleasure of inviting our two 80-ish pound dogs up on the sides with us in the mornings
It's especially great because it allows both peeps to take a midnight pit stop with no climbing over each other. Highly, highly recommended, as the bed arrangement was the only thing I don't love about our Escape.