Hi t-man,
The Aspen has 6" of Talalay latex with an inch of supersoft polyfoam in the comfort layer (within the amount that I consider OK) and then 4" of 1.8 lb polyfoam in the base layer. The Pure Latex Bliss mattresses use all Talalay latex with no polyfoam. In other words … the PLB line uses higher quality materials from top to bottom while the Aspen uses mostly the same material (Talalay latex) in the most important upper layers.
The “value” of the PLB would depend on the price that it’s selling at (the advertised prices are controlled but the actual selling prices can vary). The Aspen is good value at its regular price. Of course the PLB uses more latex and no polyfoam so it would reasonably be expected to cost more. There may also be a difference in the covers.
The other advantage of the PLB lineup is that they have several models which lets people choose which one best fits their needs and preferences while Denver Mattress only has two “mostly latex” mattresses so if one of these doesn’t work for you then that’s the end of the line as far as latex there.
If you have carefully tested both (the Aspen and the PLB model that works best for you) for PPP (Pressure relief, Posture and alignment, and Personal preferences) … then I would make the choice based on whether you believe any differences in performance, “feel”, and more costly materials throughout justifies the extra cost of the PLB model you are comparing it to. Both are good quality, and have no obvious “weak links”. In other words … between the two I would make my choice on which one best fits your “value equation”.
Phoenix