Hi srtvette,
There is more about the most important parts of the value of a mattress purchase in post #13 here that can help you make more meaningful quality/value comparisons between mattresses.
Outside of PPP (Posture and alignment, Pressure relief, and Personal preferences) which is all about how well you will sleep on a mattress, the most important part of the “value” of a mattress purchase is the quality and durability of the materials inside it which is all about how long you will sleep well.
In terms of durability and the useful life of a mattress, a mattress is only as good as its construction and the quality of the materials inside it regardless of the name of the manufacturer on the label and I would always make sure that you know the type and quality/durability of all the materials in any mattress you are considering before making a purchase so you can make sure that there aren’t any lower quality or “unknown” materials or weak links in the mattress before you purchase it (see this article).
Regardless of how it may feel in a showroom, the price of the mattress, or how well you may sleep on it initially … there is little value in purchasing a mattress that will lose the comfort and support which is the reason you purchased it in the first place and needs to be replaced much too quickly after a purchase relative to the price you paid and the loss of comfort and support isn’t covered by mattress warranties (see post #174 here).
If you can find out the type and quality of all the materials in the mattress that you would need to make an informed choice and post it on the forum then I’d be happy to make some comments about the quality and durability of the materials and the mattress as a whole. I would avoid any mattress where you aren’t able to find out the information you need to make an informed choice (see the guidelines here).
Just in case you haven’t read it yet … I would make sure you’ve read the mattress shopping tutorial here which includes all the basic information, steps, and guidelines that you will need to make the best possible choice … and more importantly know how and why to avoid the worst ones.
Phoenix