Thank you, I’ve definitely gathered that higher density memory foams are preferable for the top layers. This promotional page from Bed-In-A-Box definitely confused the matters for me, however, as without knowing the actual material properties, I think it might not be as straightforward of a comparison to just go by densities? (but then again, it’s information provided by the manufacturer, so it’s in their best interests to present their products in the best light):
Specifically, this is what B-i-a-B claim:
"There is such a thing as too much density. The main complaint of memory foam mattress owners is that the foam gets too hot or that it takes too long to rebound when turning over – interrupting sleep. These are the direct results of too much density. Mattresses with 5 lb. density and greater are commonly cited as being too “gooey” when warmed by the body and exhibit the problems just cited. Another reason higher density foams perform poorly is because of older memory foam technology.
*** If a company is using outdated foam technology, their foam will stiffen when left in an area cooler than 60 degrees. Our foam will not stiffen. "
"Memory foam density and softness numbers may not necessarily be a good way to determine memory foam quality. The chemicals which are used to make memory foam can vary greatly from manufacturer to manufacturer and even from “pour” to “pour”.
The U.S. is currently being flooded with Chinese memory foam that is supposed to have adequate density such as “5.3lb” but which tends to exhibit poor characteristics. These characteristics include slowness to rebound, getting harder as the room temperature gets cooler, heat build-up after laying on it for a while and chemical smells. These smells are often caused by chemicals and take a very long time to dissipate from the mattress and may be harmful and even carcinogenic. There are no regulations on the purity and safety of Chinese or any other memory foam. Even though it is inexpensive, there may be a health price to pay."
(Regarding the smell, I know both Tempurpedic and Bed-in-a-Box are not rated well on SLTD for outgasing properties, so that’s probably a wash).
I should have specified that it was not the subjective comfort difference that I was looking to find information on, but rather the rebound properties of the materials in Tempur-Pedic’s Contour Elite and B-i-a-B’s 3" gel foam + 8" polyfoam mattresses. Basically which will retain its shape with regular rotation better after 1-2-5 years, and which will be better for changing sleep position–I mean say you sleep in one position for 2 hours, and the foam molds around you very well, and when you try to change position, the depressed points don’t reinflate quickly enough, such that there are heavy dips in some areas.
It sounds like you’re mostly recommending the Tempur-Pedic Contour Elite? I can’t tell if that at $1250 for Queen is going to be long-term better than B-i-a-B for $800-$1300 ($500 difference for the Tencel covering???)