Hi sleepyjoe870,
You can read a little more about the materials in the Tuft & Needle mattress in posts #2 and #6 here. While they may be using a variation of the high performance polyfoam that is different from other manufacturers in terms of its specific density, formulation, or firmness … it would be very similar to other high performance polyfoam made by the same or other foam pourers and used by many other mattress manufacturers in terms of quality/density and durability. Energex in general is a high quality/density and durable high performance polyfoam material regardless of its specific firmness, density, or formulation.
There is more about the 3 most important parts of the “value” of a mattress purchase in post #13 here which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability (how well you will sleep), durability (how long you will sleep well), and the overall value of a mattress compared to your other finalists based on suitability, durability, and all the other parts of your personal value equation that are most important to you (including the price of course and the options you have available after a purchase to fine tune the mattress or the exchange return options that are available to you).
The Dreamfoam Arctic Dreams mattress is very new and I don’t know the specifics of the materials inside it so if you can find out the information listed in this article about the density of the foam layers inside it then I’d certainly be happy to make some additional comments about it as well.
Phoenix