Hi jacksonjm,
The first place I would start your research is the tutorial post here which has all the basic information, steps, and guidelines that can help you make the best possible choices … and know how to avoid the worst ones.
Outside of testing a mattress for PPP (Posture and alignment, Pressure relief, and Personal preferences) … a mattress is only as good as its construction and the quality and durability of the materials inside it. Without knowing the specifics of what is inside your mattress … there is no way for you to identify any weak links in the mattress or make meaningful comparisons to other mattresses. No matter what a mattress feels like in a showroom … there is little value in buying a mattress that uses lower quality materials that soften or breaks down too quickly and you can’t “feel” the quality of the materials inside. Lower quality materials can feel just as good as higher quality materials … for a little while. I would never buy a mattress where I didn’t know the quality of the materials inside it … especially in the comfort layers which are generally the first to break down … the risk is just too high. This would be particularly true with major brands.
I would also make sure that you have done some careful and objective testing on a mattress because basing your choices on subjective comfort or the “showroom feel” of a mattress can have lower odds of making a suitable choice than random chance alone (see this study)
It’s really not possible to have an opinion of a mattress that you don’t know what’s inside it but the odds are very high that like most of the Simmons mattresses there are some low quality/density materials in the comfort layers that will likely soften or break down much too quickly. As you can see in the guidelines here … I would avoid it.
I’m happy to share my thoughts about any mattress but the retailer or manufacturer would need to provide you with the type and thickness of all the materials and components from the top down (so that they add up to the thickness of the mattress), the density of any polyfoam or memory foam, and the type or blend of any latex in the mattress. Once you have this (and of course you’re welcome to post it on the forum if you’d like my comments) it’s possible to identify any weak links in the mattress and make meaningful comparisons to other mattresses.
There are too many unknowns, variables, and personal preferences involved for anyone to suggest “what” mattress to choose for someone else but I’m happy to help with “how” to choose. Following the steps in the tutorial post has the highest odds of making the most suitable choice that is the best match for your personal value equation.
A mattress is about PPP which is more than just comfort (which is more subjective). Durability is also an important part of the value of a mattress purchase. A mattress that will last you for 20 years that isn’t a good match for you in terms of PPP and that doesn’t provide you with quality sleep would have little value but on the other hand a mattress that is “amazing” and provides you with the best sleep of your life but uses low quality materials and softens or breaks down so you lose the comfort and support that was the reason you bought it in a year or two would also have little value. I think it would be a bad idea yes.