The main chamber on mine is quite thick and not dense at all. It's saturated with air pockets and I think it's that that insulates so well. I was suprised when I picked up the main chamber for the first time, I thought wow, this thing is gonna be heavy, but I can pick it up with one arm. In one of the pics above youcan see the thickness. That's a smooth wall with no rolled lip. It's about an inch thick.
The other problem I found was it's hard to get a good seal between the lid and main chamber. I took me a lot of grinding and mating the two. I was going to put a gasket there but cbf lol.
Mine holds temps better than the UDS. It's only problem is it's small and only holds enough space for 1 spatchcocked chicken or one whole and a fattie.