What makes the 21SSL interesting is how much livability Forest River packed into an expandable design. Square bunk ends with aircraft cable and individual fan/light combos give the sleeping areas a more permanent feel than most pop-outs. Inside, you're getting solid wood cabinet doors, solid surface kitchen countertops, a recessed cooktop, and full-size double-door refrigerator, which is a step above what you'd expect at this size. There are actually two mounted TVs included standard, plus a wifi booster and outside speakers for the awning area. The enclosed underbelly and torsion axle suspension are solid practical additions for anyone planning to use it beyond fair-weather weekends.