Not a hard side, but I have a 2015 SS-1251. As far as I can tell, they haven’t changed significantly over the years. I’ve had mine for 3 years now and I’m happy with it overall. It’s solid enough and has held up well. I haven’t had any trouble with any of the systems. The behind the scenes finish work leaves something to be desired. For instance, routing of the plumbing and wiring is sub optimal. This may be true of all campers though. I would recommend looking inside all of the compartments with a flashlight when you go to look at one. Pulling out the drawers will also reveal some of the inner workings.
I’m happy to answer any specific questions you may have. As far as I know the soft side units have the same appliances as the hard side units.