Why? They are absolutley pants! They are not at all warm, when damp they are useless but they look cool.
Why not make your own for less than a tenner? You can have a fibre pile one made from a mattress topper that is slightly more bulky, a hundred times warmer and will keep you warm even when wet/damp.
I've got an unused ponch liner in woodland camo that I don't need. PM me if you want to sort out a swap
Cheers
Rat
Background for photography!