Air beds have been around for a long time, and Select Comfort is the foremost contributor. Select Comfort markets this technology as adjustable for each sleeper and asks “what’s your sleep #?” Your sleep number is the amount of air you use to feel the air chamber. At a firm level an air bed offers good support. But like any firm surface it creates pressure points. When the air volume is lessened an air mattress loses its ability to push the hips up into proper relationship with the shoulders.
Many people who sleep on an air bed at a lower level of air end up with a back problem from lack of support. The other problem with air bed technology is the possibility of mold. An air chamber tends to be fairly cool. When you put cushioning on top of it like foams there is a difference in temperature that leads to mold and fungus growth.
This is especially evident in warm and humid climates. There has been class action lawsuits to compensate many air bed buyers in Florida. Many air bed manufacturers recommend that customers open the bed and wipe the surface of the air chamber with bleach every 90 days to prevent the growth of mold. So while air is cheap and easy to ship it lacks the ability to support the body properly and is prone to contamination in warmer climates.