Hi jamaes22,
2.6 lb polyfoam is a very high quality and durable material (and is higher quality/density than you will find in the support core of most mattresses including the BestMattressEver and the Kiss mattress) although the deeper layers of a mattress will have less effect on the overall durability and useful life of a mattress than the comfort layers. The Talalay latex is also a very high quality and durable material (latex in general is the most durable of all the foam materials) so neither one of these mattresses have any lower quality materials or weak links that would compromise the durability of either one of them for any weight range although of course they will “feel” different.
You can see my comments about the quality/durability of the BestMattressEver and the Kiss mattress in the previous post I linked but neither one of them use any lower quality materials or have any weak links in their design that would compromise their durability relative to any weight range either.
All of these mattresses use materials that are higher quality and more durable than the minimums in the quality/durability guidelines that I linked in my previous reply so it would be reasonable to expect any of them to last 10 years or longer.
There is more information in post #9 here about the different ways that one mattress can “match” or “approximate” another one. Every layer and component in a mattress (including the type, thickness, and firmness of each layer and component and the cover) will affect the feel and performance of every other layer and component and the mattress “as a whole” so unless you are able to find another mattress that uses exactly the same materials, components, and design (which would be very unlikely) then there really isn’t a way to match or compare one mattress to another one in terms of “comfort” or “feel” or PPP (Posture and alignment, Pressure relief, and Personal preferences) based on the specifications of the mattress. When there are more than very minor differences between two mattress then you will find that different people with different body types, sleeping positions, and individual preferences and sensitivities can have very different opinions about how two mattresses compare.
Again … the only way to know how any mattress will “feel” for any particular person will be based on your own actual testing or personal experience. Trying to describe how a mattress will feel would be something like trying to describe how a particular recipe will compare to another one when the person you are describing it to doesn’t have a suitable frame of reference from actually trying something that is the same or very similar (and even then different people will also have different opinions about how two recipes compare as well).
The transition layer in the Kiss mattress would be less resilient or “springy” than the transition layer in the BestMattressEver but how any individual person will experience the difference or which one they would prefer will depend on many variables (and this isn’t the only difference between the mattresses that will affect how they feel) including their body type, their sleeping style, and their individual preferences and sensitivities and the degree that they will feel the differences in the transition or deeper layer in the mattress.
I don’t have any personal experience sleeping on any of the specific mattresses you are mentioning but even if I had tried all of them for an extended period of time my own personal experience or my opinions about how they compare could be very different from yours so your best source of guidance about these types of comparisons will be more detailed conversations with the manufacturers that sell them.
There are hundreds of versions of latex/polyfoam mattresses and hundreds of versions of all latex mattresses that are all very different from each other so there is no specific description that will fit a whole category of mattresses. Having said that … there is more information about how latex/polyfoam hybrids compare to all latex mattresses at least in very general terms in post #2 here.
Phoenix