Realized that Stephenson's Warmlite is still in business, and now selling their air mattress separately.
http://warmlite.com/down-air-mattress-alone/ and https://backpackinglight.com/stephen..._down_air_mat/
The saw that there were 7 cm and 9 cm down filled air mattresses. https://smile.amazon.com/Exped-DownM...nCrt=my-impact
Though exped is no longer sold by REI.
http://www.summitpost.org/outdoor-ge...r-mattress/548
I was wondering why they aren't more popular.