Hi nina__online,
I think that the best suggestion I can make would be to “reset” how you are looking for a mattress.
The first place I would start your research is the mattress shopping tutorial here which includes all the basic information, steps, and guidelines that can help you with how to make the best possible choices … and perhaps more importantly know how and why to avoid the worst ones (including the major brands along with any mattress such as the Sleep To Live mattresses that either can’t or won’t provide you with the information you need about the quality and durability of the materials in their mattresses that you would need to make an informed choice).
Two of the most important links in the tutorial that I would especially make sure you read are post #2 here which has more about the different ways to choose a suitable mattress (either locally or online) that is the best “match” for you in terms of “comfort” and PPP that can help you assess and minimize the risks of making a choice that doesn’t turn out as well as you hoped for and post #13 here which has more about the most important parts of the “value” of a mattress purchase which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability (how well you will sleep), durability (how long you will sleep well), and the overall value of a mattress compared to your other finalists (based on all the parts of your personal value equation that are most important to you).
There is more about the bed match system in this topic and you can read a little more about pressure mapping systems in post #2 here and post #4 here. While they can be helpful … I would be cautious about overemphasizing their importance compared to what your body tells you and using the testing guidelines in the tutorial because they can help more for pressure testing than spinal alignment (pressure relief is not the same as spinal alignment and a mattress that does a great job relieving pressure is not necessarily the best choice in terms of alignment).
The “best” mattress is a mattress that relieves pressure and that keeps your spine and joints in neutral alignment over the course of the night. Each person is unique however so a mattress that works well for one person may be completely unsuitable for someone else to sleep on.
I don’t have any specific suggestions or recommendations because the first “rule” of mattress shopping is to always remember that you are the only one that can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved that are unique to each person to use a formula or for anyone to be able to predict or make a specific suggestion or recommendation about which mattress or combination of materials and components or which type of mattress would be the best “match” for you in terms of “comfort” or PPP (Posture and alignment, Pressure relief, and Personal preferences) or how a mattress will “feel” to you or compare to another mattress based on specs (either yours or a mattress) or “theory at a distance” that can possibly be more accurate than your own careful testing (hopefully using the testing guidelines in step 4 of the tutorial) or if you can’t test a mattress in person then your own personal sleeping experience (see mattress firmness/comfort levels in post #2 here).
The issues you are facing may have less to do with the mattresses and more to do with your back issues so there may not be a perfect solution until your back issues have been dealt with and healed and “best possible” may be the most realistic goal.
There is more detailed information about the most common symptoms that people may experience when they sleep on a mattress and the most likely (although not the only) reasons for them in post #2 here.
There is also more about primary or “deep” support and secondary or “surface” support and their relationship to firmness and pressure relief and the “roles” of different layers in a mattress in post #2 here and in post #4 here that may also be helpful in clarifying the difference between “support” and “pressure relief” and “feel”. As you can see a mattress that has softer comfort layers and provides better pressure relief can also be “more” supportive in terms of providing good alignment as well because it can still have a firmer support core to provide primary support and the softer comfort layers can provide better secondary support under the more recessed parts of your sleeping profile along with better pressure relief.
These posts are the “tools” that can help with the analysis, detective work, or trial and error that may be necessary to help you learn your body’s language and “translate” what your body is trying to tell you so you can make the types of changes or additions to your mattress that have the best chance of reducing or eliminating any “symptoms” you are experiencing out of the options that are available to you.
While careful testing with a local purchase can have very high odds of success … for those that are making an online choice that they can’t test before a purchase, have a history of choosing mattresses that are unsuitable for them even if they have tested them, have body types or health considerations that are more challenging and make choosing the most suitable mattress more difficult, or that for whatever reason are more uncertain about whether their choice is “right” for them … then the options you have available after a purchase to fine tune the comfort or support of the mattress or to exchange or return the mattress or individual layers can become a much more important part of each person’s personal value equation. Of course the other side of this is that exchange or return options are built in to the cost of a mattress so they can add to the cost of a mattress and the majority of people who don’t return or exchange a mattress or a layer are the ones who pay for the minority of people who do.
In many cases the knowledge and guidance of the retailer or manufacturer you buy from can also be one of the most important parts of the “value” of a mattress purchase.
The tutorial includes several lists to links of the better online options I’m aware of (in the optional online step) and may of these have great return or exchange policies and if you let me know your city or zip code I’d be happy to let you know about the better options or possibilities that I’m aware of that are close to you as well.
Phoenix