Hi MitchK,
An adjustable bed would be equivalent to a foundation or platform bed that has a firm, evenly supportive, and non flexing foundation and other than making sure your mattress can bend easily without damage and is suitable for use on an adjustable, it wouldn’t have any effect on which mattress you choose in terms of PPP.
Most foam mattresses and pocket coil mattresses and some innerspring mattresses with helicals that have been customized for use with an adjustable (such as a hinged border rod) would be fine with an adjustable but it’s always best to check with the manufacturer or retailer of your mattress to confirm that it would be a suitable choice and that an adjustable bed meets the warranty criteria.
They are certainly a good quality/value choice for those that are in a lower budget range and like the idea of sleeping on a basic and well designed polyfoam mattress although they are certainly not unique in having low or “fair” markups which are the norm with better manufacturers and retailers. Their infographic about typical stores is greatly exaggerated and more about marketing than anything else. I can’t think of any retailers that have actual selling prices (which are normally in the range of about 50% of the often fake “suggested” retail price) that are marked up anywhere close to a fraction of the 3 - 400% markup that the infographic implies is the norm in the industry.
The better options or possibilities I’m aware of in the Denver area are listed in post #2 here.
You can see the Information I would want to know about any mattress I was considering and the quality guidelines I would use in post #4 here.
Phoenix