Hi draxtmu,
I’m not Smccormick22 of course and hopefully they will see your post and be able to make some comments but in the meantime I can make a few comments as well.
How a mattress is holding up in only a year for any particular person won’t tell you much about the durability of the materials in a mattress that is designed to last much longer than that and you would need a large number of reviews after 5 - 10 years that included specific information about the body type and sleeping style of the people sleeping on the mattress (durability is relative to the person sleeping on a mattress … see post #2 here) to be able to see any meaningful patterns about the durability of any mattress that doesn’t have any weak links in the design.
There are much more reliable ways to assess the durability of a mattress or whether it has any weak links in its design than using reviews (see this article and the quality/durability guidelines that it links to). There is also more detailed information about the many variables that can affect the durability and useful life of a mattress relative to different people in post #4 here and the posts it links to.
ILD is a “comfort spec” and not a “quality spec” and isn’t really important to know when you are testing a mattress in person because your body will tell you whether a mattress is a good match for you in terms of PPP much more than knowing the ILD of the layers. Most people wouldn’t have the knowledge or experience to know how different combinations of ILD would work for them with different types of latex anyway (and ILD alone isn’t the only spec that will make a difference in how the mattress feels and performs) so for most people, knowing the ILD of the layers would have no practical use and may be more confusing than helpful. There are many manufacturers that treat the ILD of their mattresses as proprietary (see post #10 here)
There are a number of reasons for using a polyfoam quilting layer over latex. One of them is usually for some additional softness/plushness but this can also vary depending on the quilting pattern and the foam used because it can also be used to create a firmer sleeping surface. Another is that latex is a very resilient material and there are many people that prefer a less resilient and more “relaxed” sleeping surface vs sleeping directly on the latex. There are other reasons as well and there is more about the pros and cons of different types of quilting layers and materials in post #12 here and the posts it links to. The type, firmness, and thickness of the quilting layers and the latex layers as well as the body type and sleeping positions of the person will also affect how the mattress contours to the shape of the body.
When you are comparing mattresses it’s always a good idea to make “mattresses to mattress” comparisons and then you can compare the “value” of the different foundation options you have available separately. There isn’t a formula that can be used to assess the “value” of a mattress based on the “commodity cost” of the materials or components inside it (there are too many unknowns and variables involved) and the “value” of a mattress is also relative to how it compares to your other finalists or to other mattresses that are available to you. A mattress that is “good value” for one person or in one area may be “poor value” for someone else that has different needs and preferences or that lives in a different area that has different mattresses available to them.
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 comparisons with other mattresses based on criteria that are based on more “real life” considerations than the raw material cost of the materials and components in a mattress. Post #2 here also includes some other latex/innerspring hybrids that you can use for comparison purposes (some would be more and some would be less). There are also other variables that can affect the cost of similar mattresses made by different manufacturers in post #14 here and the type of innerspring and the amount, type, and blend of the latex and any other materials and components in each mattress you are comparing (including the cover) and many other factors will all have an effect on the cost of manufacturing a mattress and on making “apples to apples” comparisons based on materials alone so it’s very difficult to assess the relative value of a mattress based only on the materials and components inside it unless all the materials and components in two mattresses you are comparing are very similar or identical.
Phoenix