Hi tkearn,
Thanks for your feedback and for adding the results of your research to the forum.
Your comments are also relevant to some of the things that can cause confusion with many consumers, some of the differences between marketing information and more accurate information, and some of the “fuzzy lines” between them.
First of all … you are certainly correct that Tuft & Needle isn’t a mattress manufacturer and they don’t have their own factory. What they do is design and test their own mattress and then as you pointed out they have it manufactured by a foam fabricator. Most retail stores purchase their “brand name” mattresses from a mattress manufacturer who in turn purchases the individual components from a foam supplier such as Abad who in turn purchases their bulk foams from a foam manufacturer which they then cut or fabricate in various ways. In some cases even mattress manufacturers will outsource some of the parts of their mattresses to other companies (such as purchasing pre-made quilted covers rather than making their own with a quilting machine or buying layers that are already cut to a certain thickness by a fabricator rather than buying a foam bun from a foam manufacturer and then cutting the layers themselves). In other words … there are many “layers” between raw materials and a final mattress and there is a great deal of overlap between each layer as the industry looks for cost efficiencies. Some foam manufacturers are also making mattresses for example and there are even some mattress manufacturers that are pouring their own foam.
What this means is that Tuft & Needle has eliminated some of the steps compared to some of the mattresses you would find in a retail store but they are not an actual mattress manufacturer and would be more correctly called a reseller.
In terms of foam densities … this is also a “fuzzy area”. When a mattress manufacturer orders foam they will generally specify a tolerance that is acceptable to them because foams aren’t produced in exact densities or ILD’s. For example they may order a 2 lb polyfoam with a +/- tolerance of .2 lb which means that the foam they actually receive would be somewhere in between 1.8 lbs and 2.2 lbs. In practical terms … it would normally mean that the foams that they received would be on the lower end of the range unless they specified otherwise. Larger spec tolerances would be less costly than tighter spec tolerances.
I think that it would be reasonable that a foam that was around 2 lb could easily be 1.9 lb but I also agree that a 1.8 lb polyfoam is a fairly wide variance. This would be especially true if it was ordered as 1.8 lbs rather than 2 lbs. You can see an exampleof a manufacturer that specifies the tolerance range of their foam densities here and the range for their polyfoam density is +/- .1 lb.
While they are a good quality/value option that has low risk because of a generous return policy (that also benefits local charities similar to the World Bed program that Interactive Bedding Solutions also sponsors) … I also agree that some of the information on their site (including this page about typical margins or markup with other manufacturers) is somewhat misleading and exaggerated (see post #2 here) and I wish they would change it to something more realistic and accurate that doesn’t imply that most retailers or factory direct mattress manufacturers are marking up their mattresses by 500% over their wholesale cost or that their comparisons were more “apples to apples” based on realistic industry averages.
There are many “layers” between the raw chemicals or materials used to make mattress components and a mattress that is sold to a consumer and each distribution layer has their own margins. Some of these include the chemical companies that make the chemicals used to make polyfoam or memory foam or synthetic latex, the plantations that harvest the rubber used to make natural latex, the foam manufacturers that pour the cores, the manufacturers that use raw fibers to make covers or fabrics, the foam manufacturers that pour the foam, the foam fabricators that cut or further fabricate the foam, the mattress manufacturers that make the mattresses, the distributors that store and ship the mattresses to the point of sale, the delivery companies that actually ship the mattresses, and the retailers themselves. It’s also true that there is trend in the industry for each of these levels of production and distribution to integrate with others (such as foam manufacturers or foam fabricators who make mattresses rather than just supply components) to realize cost efficiencies and lower the price of their mattresses so from this perspective Tuft & Needle has eliminated some of the layers in the supply chain.
It’s also true however that they are not a mattress manufacturer and that there are other options that use the same materials or provide different or more choices that are in the same value range.
You certainly have a good quality/value mattress and the return policy also adds to the value of an online purchase but the points you made also make clear that they are “not quite” as different from other good quality/value options as some of the information on their site would have you believe … if you are making apples to apples comparisons with other good quality/value manufacturers or resellers (who are doing the same thing as they are).
Their comparisons would be more accurate if you compare them to the mainstream industry (although they are still exaggerated) and I wouldn’t hesitate to buy a mattress from them if I believed their specific design and somewhat limited options were suitable for me along with the lowered risk of their return policy but they are not nearly as accurate if they are compared to some of the other options that are available from the better value mattress manufacturers or resellers that are available to more “informed” consumers.
Thanks again for your post and for bringing up some good points 
Phoenix