I would ask someone who has ordered one recently to give you a review. Stephenson fixed the valve and baffle problems but I don't know about the fabric slipperyness...and you can always drip a line or two of silynyon on it.

The best part of the DAM was it worked very well with the Warmlite bag for use in really cold weather. Used in that context, it might do very well what you're planning to do.