"that i might need the 20D nylon Revelation for the extra water-proofing?"
I have a GoLite 20F quilt but have wondered about this. Even if the encapsulating material is 100% cuben, would water vapor still be passable through the seam? And how hard would a cuben quilt be to dry? I'm wondering if it's best to get a synthetic for humid climates with a breathable shell? Skurka did in Alaska... can't imagine going that many days in down without it losing a ton of loft and gaining a ton of moisture weight.