I have been looking at buying some down, and compared to thru-hiker the FF down seems like a really good deal. However I just spent 20 minutes browsing their site and I don't see any way to order down from them directly. Jerry, did you contact them directly?
Edit: I can't find anything anywhere about cuben fiber down jackets or vests. If cuben work for quilts, it seems just as good to use it for a vest. What weight would one use? I was thinking the .51oz/sq yd stuff from zpacks. if I used thru-hiker's down, made the vest a pull-over style with only a 1/2 zip, it would weigh significantly less. is .9 the nominal weight of pertex or the actual? if its the nominal, you would save 1.8 oz on the fabric, plus about 1/2 an ounce on the down, and perhaps another 1/2 an ounce by shortening the zip. thats a total weight saving of 2.8 oz, making the finished weight under 6 oz! plus with the vapor barrier effect of the cuben, it might be slightly warmer too. the only trouble is it would increase the cost to about $115 (45 for the down, and about 60 for the cuben, buck or two for the zip). still, thats less than the montbel ex light down vest, but you have 3 times as much down in there.
hold on, that doesn't add up. 4.5oz of down, plus 3sq yards fabric at .5 osy totals 6oz already, and thats without thread or zip. perhaps .9 is the actual weight of pertex? or maybe the pattern actually uses less than three sq yds of fabric?