I was looking through an old (July, 2008) issue of Motorcycle Consumer News and saw a comparison between two air cushions. The Air Hawk has been around for several years, but a newcomer, Freedom Air, is challenging them.
They tested them on a BMW R1150GS. They used a "Small Cruiser" Air Hawk, and a "Sport Touring" Freedom Air. Long story short, the Air Hawk offered a 25 percent improvement over the stock uncomfortable seat, while the Freedom Air provided a 70 percent improvement. Info:
www.longeride.com