Weathering Tents.

I actually bought on of these, http://www.blackwolf.com.au/turbo-lite/turbo-lite-plus/
It's a different material than the poly-cotton.

Ah yes, sorry Krackar, my mistake. Thought they were same material from when I was comparing them some time ago. Should have double checked before I posted incorrect information instead of relying on my failing memory.

Not sure why you would question the manufacturers recommendations though. I reckon they would be better equipped to know what needs to be done to their own products than anyone else.