Hi sallyc,
Welcome to the site … and I’m glad you found us :).
There is more information about the 3 most important parts of the “value” of a mattress purchase in post #13 here which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability (how well you will sleep), durability (how long you will sleep well), and the overall value of a mattress compared to your other finalists based on suitability, durability, and all the other parts of your personal value equation that are most important to you (including the price of course and the options you have available after a purchase to fine tune the mattress or any exchange/return options that are available to you).
While I can’t speak to how a mattress will feel or how different mattresses will compare in terms of comfort and PPP (Posture and alignment, Pressure relief, and your Personal preferences) for someone else … outside of “comfort” and PPP the most important part of the value of a mattress purchase is durability which is all about how long you will sleep well on a mattress. This is the part of your research that you can’t “feel” and assessing the durability and useful life of a mattress depends on knowing all the specifics of its design and construction and the type and quality of the materials inside it regardless of the name of the manufacturer on the label or how a mattress feels in a showroom (or a hotel room) or when it is relatively new so I would always make sure that you find out all the information listed here so you can compare the materials and components to the quality/durability guidelines here to confirm that there are no lower quality materials or weak links in a mattress that would be a cause for concern relative to the durability and useful life of a mattress before making any purchase.
Unfortunately the description you posted didn’t include all the information I would need to make any meaningful comments about the quality or durability of all the materials and components in the mattress or the mattress “as a whole” so if you could provide all the information in the article I linked about the type, thickness, and density of all the foam layers in the mattress I’d certainly be happy to make some comments about it.
The pocket coil is a good quality component but the deeper layers or components of a mattress aren’t generally the weakest link of a mattress anyway.
The 2.5 lb high density polyfoam layer is also a high quality and durable material but I would want to know the thickness and density of all the foam layers in the mattress.
Polyfoam certainly isn’t an organic or a “natural” or a “green” material although some versions of polyfoam do use a relatively small percentage of plant based polyols in their chemical formulation to replace the petrochemical polyols that are most commonly used (see post #2 here).
There is also a lot more information in post #2 here and the more detailed posts and information it links to about safe, natural, organic, “chemical free”, and “green” mattresses and mattress materials that can help you sort through some of the marketing information and terminology that you will encounter in the industry and can help you differentiate between them and answer “how safe is safe enough for me” or “how natural is natural enough for me” or “how green is green enough for me” and that can help you decide on the type of materials and components you are most comfortable having in your mattress or on the certifications for harmful substances and VOC’s that may be important to you. These types of issues are complex and are generally specific to each person and their individual sensitivities, circumstances, criteria, beliefs, and lifestyle choices.
Phoenix