Hi demos83,
Feel is very subjective and relative to each person’s experience and how they experience different sensations and is as much an art as a science but in very general terms you will “feel” changes to layers that are closer to the surface more than you will with changes to layers that are deeper in your sleeping system. There are also different types of softness and firmness that contribute to “feel” in different ways and some people may be more sensitive to one type of feel than another (see post #15 here).
There would be many different combinations that were “in between” both of these that would fine tune and affect how each one feels to different people to different degrees but changing any layer to a softer version will soften the “feel” and changing any layer to a firmer version will have a firmer “feel” and changes to deeper layers will have less effect for most people than changes to upper layers. Body type will also play a role since heavier people will sink in more deeply which can affect how much they feel changes to deeper layers and some people are just much more sensitive to smaller changes as well and will notice variations that others can’t feel at all.
For example if you were to change the third layer from the top in the first mattress from medium to firm some people would notice a firmer “feel” and if you were to change the second layer from the top in the first mattress from medium to firm then the firmer “feel” would be even more noticeable yet and a larger percentage of people would feel the difference.
There is more about the different ways that one mattress can “approximate” another one in post #9 here but if two mattresses have the same design and use the same type and blend of latex in the same thickness, and firmness level in all the latex layers and have a cover that is functionally the same as well then they would be very close approximations that would feel the same outside of the normal variations in firmness level between latex layers that have the same firmness rating (ILD’s are never exact … see post #6 here). If there are any differences in any of the layers and components then they will either have a cumulative effect or an offsetting effect depending on the number, type, and degree of the differences. I would also confirm that both are using certified organic Dunlop because while this may not make a difference in how the mattress feels (if they are the same density/ILD) … it may be important to you for personal reasons and it can make a difference in the cost (certified organic Dunlop latex is more costly than 100% natural Dunlop latex). Again … this is more an art than a science that can only be confirmed with personal experience.
I didn’t realize that SleepEZ had the option for a 15" component mattress (I had never asked them this) and I don’t know of any other manufacturers that would have this options available so you would need to call the members that make component latex mattresses that use organic Dunlop and have combinations of 3" layers and ask if they can make a 15" mattress with five 3" layers (they are listed here) and that also have the option for certified organic Dunlop layers (vs 100% natural Dunlop).
When you have eliminated all the options that don’t meet your criteria and you are down to finalists that are between “good and good” and there are no clear “winners” between them then your final choice (see post #2 here) would be a matter of “best judgement” based on your more detailed conversations with each of them and all the objective, subjective, and intangible parts of your personal value equation that are most important to you (including things like delivery times, return or exchange options, prices, the importance to you of buying a mattress that you can test locally, any bonuses that come with the mattress etc). You are in the fortunate position that either of them would most likely be a great quality/value choice that you would be happy with.
Phoenix