Hey folks, thought I'd chip in our $.02 on the Roofnest Falcon here:
On the specific question of internal space when closed, yeah it ain't much! What you see in the video at roughly the 10m mark is, besides the 3" foam mattress, a 'bottom sheet' of an unzipped fiber fill sleeping bag, a simple thin cotton top sheet, and Roofnest's thin and highly compressible down blanket. We initially tried just sandwiching two unzipped sleeping bags but that was a fail, too thick, and pillows are totally out of the question. We did just place an order with CustomLinensDirect.com for fitted mattress pad & bottom sheet for the Falcon's 81x47x3 mattress, so hopefully that'll fit even better...more on that when they show up and we can try 'em out.
-c