That is interesting. The picture of the upright trailer looks like the old Elkmont 26, which was made from ~2009-2011, until the company went bankrupt.
We had an Elkmont 24 upright which was a well-designed, single axle 24' trailer w/o a slide. Fully loaded for Florida, it only weighed 4000#, empty it was closer to 3000#.
They are definitely just summer trailers though. Their lightweight design comes from only 1" Al laminate foam walls and roof. No wood except in the floors which were 2" Al foam laminate with a layer of 1/4" plywood. You could actually kneel on the roof, the laminate was that strong.
We really enjoyed ours after getting the initial problems fixed. The death of the founder and subsequent bankruptcy during the post-2008 mini-depression didn't help quality control.
Just sold ours a month ago.
2014 ORV Timber Ridge 240RKS,8500#,1250# tongue,44K miles
690W Rooftop + 340W Portable Solar,4 GC2s,215Ah@24V
2016 Ram 2500 4x4 RgCab CTD,2507# payload,10.8 mpgUS tow