Hi NeedSleepInMI,
While there will be some softening initially … latex is the most durable foam material (and the blended Talalay is more durable than the 100% natural Talalay) and will soften and break down more slowly than other types of foam material. My only caution would be to make sure you have confirmed that the mattress is a good match for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) since as you mentioned it does have relatively thick and soft comfort layers but if it’s a good match for you then there are no weak links in the mattress in terms of durability.
Whether they would be a better choice for you would really depend on the parts of your personal value equation that are most important to you and your comfort level with an online purchase and that’s something that only each person can can answer for themselves. All of the mattresses you are mentioning use similar materials (latex) so none of them would have any weak links in terms of quality or durability. Once you are down to final choices that are all between “good and good” then which one would be “best for you” would really depend on all the objective, subjective, and intangible criteria that you feel strongest about.
Some stores that sell PLB offer a comfort exchange and some don’t and the benefits would depend on your confidence in the suitability of your choice in terms of PPP. Comfort exchanges are built into the retail cost of a mattress so the people who exchange a mattress pay for the ones who don’t.
There is really no “correct” or “incorrect” when it comes to the choice of materials in your mattress as long as any mattress you choose uses good quality materials (each type of material has lower quality and less durable versions and higher quality more durable versions) and there are no weak links in the mattress. The choice between different materials is always a preference choice that depends on each persons criteria and what they prefer and isn’t a “better/worse” choice.
Phoenix