Thick or thin walls?

[malconium]

My 1973 31' Sovereign International has had most of the interior removed. I will need to rebuild pretty much everything including the walls. Fortunately most of the aluminum channel that used to attach the walls appears to still be there (on the floor in the back of the trailer). I also have one of the walls left that I can use as a template to get the curve right.

My question is this:

Is it generally thought to be a good idea to stick with the thin walls and original type of mounting or is anyone using something thicker (for example: some form of sandwich panel for light weight)? If thicker how are you attaching it?

Malcolm