Not to start a war between light vs. heavy, full profile vs. mid profile, and all the other differences, let me lay my reasoning on the table and let you decide since I weighed all the options before choosing what some here seem to consider and inferior product. 1st difference, the light weight units are considered a mid profile 5th wheel, vs the full profile. I'm just under 6' and I can't really stand upright in the front bedroom, but I was OK with that and part of the trade off I was willing to make for a lighter trailer. 2nd, the frame is just as rigid as the other trailers with the same 10" steel beams, but smaller overall length, and depending on the gvwr have the same axles as the bigger units. The E30 we got was the largest lightweight they made, has dexter 5200# axles and an overall length of 34+ feet. I love the quality and look of our new lightweight trailer and it has all the options our family needed and still kept the gvwr just under 12K#. We compared it to a few SOB lightweight trailers and have to agree with others, I wouldn't buy them due to 8" frames vs 10" and just cheaper feel than the Elkridge lightweights. I even heard from other Elkridge owners that just the changes from their 2013 "express" models to my 2015 "extreme light" has been a huge difference, so some of the people on here bashing the lightweights may not understand the newer models are just as structurally sound as their rigs.
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Also, with the extreme lights you don't get a ton of "extra" storage like the full size 5th wheels so keep that in mind too. Most of the time with the lighter models you don't get the basement storage nor like mine there isn't even a pass through or underbelly storage of any sort, and without extra structure (frame below and walls to support the floor above) that is given for those types of storage areas that is another way they save weight.
