Hi yourconfused,
There are some sources for polyfoam in post #4 here.
I have no idea what Foam by Mail (FBM) really sells and it sometimes appears that neither do they or anyone else. They are certainly not a place that I would buy anything important from. More of my thoughts about them are in post #2 here and in post #2 here and in many other places around the forum.
There are really two ways to know the best layering for you. One is local testing with the help of good guidance on a mattress you end up buying. The second is to work with a knowledgeable manufacturer or source that sells mattresses online with specific combinations of layers and components and knows how every component interacts together and with different people. They will use a combination of averages, the experiences of their large customer base with their mattresses, and your own personal testing experiences to help you choose the best combination of materials and components out of what they have available. Some of the better choices I know of are the members of the site listed in post #21 here.
There are some guidelines in the mattresses section of the site (particularly in the “sleeping style, preferences, and statistics” pages and in the “putting the layers together” pages that can be useful as a starting point but there are so many interacting variables involved that it would generally take extensive testing or the help of an “expert” to make the best possible decisions about layering and components.
Just as an example … if you were to order a 20 ILD layer of “latex” from FBM and it was too firm … you would probably order something that was accurately listed that was softer and make a second “mistake” because what you originally ordered probably wouldn’t have been 20 ILD after all. You would have no accurate information to use a reference point for any subsequent changes.
If you choose to do it all yourself … it would take some extensive testing on different combinations of materials to give you some reference points and know how well they meet your specific and unique needs and preferences. Then you would need a reliable supplier to order materials that were listed correctly. There is more in post #15 here about the three main ways to choose a mattress (locally, through an online manufacturer, or completely on your own).
[quote] I have come from a quite nice stearns n foster firm pillowtop that lasted a good 10 yrs and then hurt me for another couple of yrs.
I also like the feel of a stearns n foster mattress but cant find any good reviews since they were bought out a few years back. Too bad I can’t get a new version of my old mattress this many years later.
[/quote]
The last decade has certainly resulted in lower quality mattresses made by major manufacturers. They now use some thick layers of low quality and low cost materials even in their high end mattresses that are the weak link of these mattresses.
Many of the more premium mainstream mattresses have a great showroom feel but unfortunately they all tend to use some lower quality materials that are the “weak link” of these mattresses and because you don’t know the details of the layering … they are also not very useful in helping with deciding on the type of materials or layering may be best for you. Even the few they make that do use higher quality materials are generally very poor value compared to other mattresses that are available and in most cases you still won’t be able to find out any meaningful information about what is really in them. At best they can provide a very general sense that certain generic combinations of materials can be comfortable for you in a showroom.
Phoenix