Hi goneagain,
The first thing I should mention is that I don’t recommend being your own mattress designer unless the challenge and experience you will gain is worth the risk you are taking (financially and in terms of the quality of your sleep) and you are prepared for the learning curve and frustration that can be involved in knowing how to put your mattress together without “backup” or guidance. I believe there are much better and less risky ways to purchase a mattress where you can use the knowledge and experience of people who do this every day to your benefit. You can read more about this in post #15 here.
The polyfoam sources that I’ve listed are sources meant to give the members here some good choices of good quality materials and access to people who can help educate you about different types and quality of foam but you will need to make the same value comparisons as you would if you are buying any other types of material or a mattress using the guidelines on the site about how to recognize better quality and value according to your own personal value equation. I would definitely not make the assumption that price is indicative of quality or value in the world of mattresses or materials.
As you can read in post #2 here and in post #2 here … I would not personally deal with Foam By Mail and I don’t trust that what they describe is what they sell. Each member though is of course free to make up their own minds about who they trust and who they prefer to deal with. My goal is to provide the information so members can make better and more informed choices.
I think this would be a mistake. Latex ILD’s don’t match polyfoam ILD’s and their mattresses are a different design completely than any mattress that uses solid layers and can’t really be “translated” into other designs.
I personally would follow the steps I listed in post #1 here to find the best possible quality and value mattress … and most importantly one that will match your personal needs and preferences … unless you can sleep on anything regardless of how it is layered. IMO … theory without extensive personal experience to translate it into something meaningful is just not a great way to go unless it is for the challenge or learning experience alone regardless of the outcome or the costs involved in any mistakes you make along the way.
Phoenix