Many years ago I worked for the C.S. Wo company in Oahu, Hawaii, selling mattresses at their mattress store. We carried a number of brands, such as Tempurpedic, Simmons, Stearns and Foster, etc. One day, the manager of our division announced that we would be carrying the Sleep Number beds. Once I got to check them out, I told him I would not be selling them. He asked why, concerned since I was the number one salesperson in the store. Here was why;

• They are an air mattress -  Ever get excited to sleep on an air mattress? No? Me neither. Usually you wake up in the morning to find the air had leaked and your butt is on the ground and you feel like you are in a hammock. But that is what a Sleep Number is: It is an air mattress with a foam top, a remote control driven pump and a great marketing campaign.
• What's wrong with an air mattress? - Other than the above stated issue, air mattresses are incapable of supporting the curve of your spine. Pump the bed all the way up, and you have a flat surface, hard and unyielding. When a bag of air has reached its limit, there is nowhere for the air to go, so it creates a firm surface. You may as well put a foam pad on the floor. That is what happens with an air mattress. And once you allow air out, the heaviest part of your body will start to sink first, just like when that cheap air mattress loses air overnight.
• It's only as good as the foam above the air mattress - What makes the mattress comfortable is the foam mattress above the air mattress. But once the foam, not a very high quality foam, starts to lose it's ability to support and distribute your weight properly, the mattress is no longer able to properly support your posture.
• Air mattresses are made with vinyl and vinyl sleeps hot - The air mattress component is made of a vinyl bag and vinyl does not breathe, leading to some consumers to sleep hot in the bed. It has even been known to accumulate sweat in and around the bladder and lead to mold issues.