Hi ejcrossi,
There is more about the different ways that one mattress can “match” another one in post #9 here but unless two mattresses have almost exactly the same design with the same type materials, the same layer thicknesses and firmness, and a functionally similar cover there really isn’t any way to know how closely two mattresses will approximate each other for any particular person outside of your own personal testing or experience.
“Feel” is also very subjective and I would also suggest avoiding using using a specific mattress as your “target” or reference point because it may not be the best possible match for you in the first place compared to other mattresses that you haven’t tried and you could end up excluding many other mattresses that may be different but could be a better choice in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences). Human memory for softness, firmness, and “feel” is also very unreliable and short term and a mattress that may feel similar to what you “remember” another mattress feels like may end up being very different than how they would compare if you were to test them side by side in real time. Instead of using a specific mattress as a reference point I would rate every mattress you consider against a common set of criteria (rather than against another mattress) using the testing guidelines in the tutorial post and based on which one is the best “match” for you in terms of PPP and all the other parts of your personal value equation that are most important to you.
The first place I would start your research is the mattress shopping tutorial here which includes all the basic information, steps, and guidelines that you will need to make the best possible choice … and know how and why to avoid the worst ones. There is also more about the three most important parts of the “value” of a mattress purchase in post #13 here which can help you make more meaningful comparisons between mattresses in terms of comfort and PPP, quality and durability, and “value”…
I would be very cautious about buying a Kingsdown or any mattress where you aren’t able to confirm the quality of the materials inside it to make sure there aren’t any lower quality materials or “weak links” in the design (see this article and the guidelines here) and Kingsdown isn’t generally transparent about the quality of the materials inside them (see this article).
While the most important part of “value” of a mattress purchase is comfort and PPP (Posture and alignment, Pressure relief, and Personal preferences) but outside of PPP … a mattress is only as good as its construction and the quality and durability of the materials inside it and the durability and useful lifetime of a mattress is also a key part of the value of a mattress. No matter how it may feel in a showroom … there would be little value in buying a mattress where the use of lower quality and less durable materials leads to foam softening and the loss of comfort and support much too quickly after a purchase and foam softening and the loss of comfort and support isn’t considered to be a defect and isn’t covered by a mattress warranty (see post #174 here).
If you let me know your city or zip code I’d be happy to let you know about any of the better options or possibilities I’m aware of in your area.
Phoenix