Just a small point ... :)
These are not actually hard sided expandable trailers - they are travel trailers with a rear bedroom slide. Hard-sided expandable trailers are like
Trail Manor or the now defunct
Hi-Lo lines of RVs.
So you are in the right forum. Hope you get the feedback you are looking for.
Based on the comments about a rear bed I have seen so far, peeves include it not being a "walk-around" so more onerous to make the beds, getting in and out of bed requires crawling to the foot of the bed, and access to the rest of the coach is quite compromised when on the road and the slide is in. But the last one is the case with most RVs with slides.