Wow, that is amazing, that insulation would help so much in a truck cab where there is so much glass!
I did not insulate my first van, because there wasn't really any wall space that wasn't covered with a foot thick layer of storage :-). That acts as plenty insulation.
I'm not sure what I'm going to do with my current, extremely slow van build.
Because it's a bigger rig, fridge and body temperature don't help as much. Certainly they do something, but I still feel the cold more.
I haven't slept in it with an all packed up, though, so I don't know what that will be like. What I would really like to insulate is the roof, but that would be tricky with condensation and all.