Hi exm,
Unfortunately US Mattress doesn’t allow for mattress returns and refunds and like many of the forum members that have come here with a similar situation you are in a somewhat difficult position where you need to exchange a mattress and are “locked in” to a store or a manufacturer that sells mattresses that I would normally suggest avoiding in the first place and where there may not be any particularly good quality/value options available to you.
Having said that … there are some suggestions and ideas in post #2 here about the two main strategies that you can use that can help you make the best of a difficult situation.
US Mattress sells more than just major brands (you can see a list of the manufacturers they carry here) but if you aren’t able to find out all the information you need about the quality and durability of the materials and components inside a mattress (see here) then the name of the manufacturer on the label won’t make much difference anyway because I would treat “low quality/density” materials and “unknown quality/density” materials in the same way (it’s generally safer to assume that any unknown layers are lower quality/density).
I would focus more on the manufacturers they carry that are transparent and that they confirm they are able to provide the information that you need about the type and quality of the materials inside them or alternatively focus on firmer mattresses that have the “least possible” amount of lower quality or unknown materials that would be suitable for adding a topper to provide any additional comfort and pressure relief that you may need.
You can read a little more about hotel mattresses in general in post #3 here and I certainly wouldn’t assume that a “hotel” mattress means that it uses higher quality materials than any other mattress. There is also more about the pros and cons of two sided mattresses vs one sided mattresses in post #3 here. While a two sided mattress would be a more durable choice than a one sided mattress that used the same type and quality of materials and components on one side of the mattress only (assuming that you flip and rotate it on a regular basis) … the only way it’s possible to make any meaningful comments about the quality or durability of any mattress (either one or two sided) would be based on knowing the type and quality of all the materials inside it (see this article) and it’s unlikely that they will be able to provide you with the information you need about their Serta hotel mattresses to make an informed choice.
I can’t speak to how any mattress will “feel” for you (which is the most important part of the “value” of a mattress purchase) because there are too many unknowns, variables, and personal preferences involved that are very subjective but all of the Serta hotel mattresses use innersprings that are linked together (vs pocket coils that can react more independently) so they will generally transfer more motion than a pocket coil mattress. There is more information about the different types of innersprings in this article and in post #10 here.
Unfortunately this probably won’t help you much because you won’t be able to return your mattress for a refund and start over again but just for reference … the better options or possibilities I’m aware of in the Long Island area (subject to making sure that any mattress you are considering meets the quality/value guidelines here) are listed in post #4 here and the NYC list that it also links to.
Phoenix