I had actually received an email from Michael back in April that said:

Over the years we've heard from some customers concerned with our cotton fabrics tendency to wrinkle after a washing. In light of that, we're now working with a 9.5 oz synthetic that has a beautiful hand and treated with a wicking application that helps pull sweat from the surface of the skin - helping the wearer stay dry. THis stuff is nice. You can sleep in this AmeriKilt and it looks like new at all times.

I will be interested in hearing more as these come to market.