Hi double_g,
This is a typical mistake that many consumers make and I would never buy a mattress based on the somewhat “false sense of security” of a comfort guarantee because knowing what changes you may need to make can sometimes be just as difficult as choosing the best mattress in the first place. As you can see in #10 in the guidelines here … I would choose a mattress as if you only had one chance to choose the right one so that a comfort guarantee doesn’t replace the need for good testing and is only used as backup insurance for something that you do everything you can to avoid (just like any insurance).
Careful and objective testing using the testing guidelines in the tutorial post can be much more accurate than you may realize for the large majority of people and is the most important part of a local purchase (see post #10 here and post #4 here). This way you are much more likely to choose a mattress where only relatively minor fine tuning is necessary if any at all and where your initial choice is at least close to your ideal.
Unfortunately I don’t have enough knowledge or information about either you or your mattress to be a good source of guidance about comfort issues and these types of more complex situations have so many variables that they are usually best dealt with in person or with a much more detailed conversation on the phone with a retailer or manufacturer if “in person” isn’t possible. I can’t see you on the mattress or feel what you are feeling. They will know much more than anyone else (including me) about the specifics of their own mattresses and how all the materials and components work together with different people based on their experience and customer feedback than anyone else and wil be your best source of guidance. Don’t forget that I have never seen or felt the mattress you are sleeping on and I have no experience with it or how the specific materials and components would work for me much less for someone else.
The more accurately you can describe your sleeping experience (types of symptoms you are having, how and where they occur, the sleeping positions they usually happen, and when you experience them) and how you would like to change your mattress then the better a retailer/manufacturer can help you with suggestions that can help you make that change within the limitations of what they have available.
Having said that … there is more information in post #2 here and the posts it links to which talks about some of the more common symptoms that people may experience on a mattress and some of the possible reasons behind them that you may recognize in your own sleeping experience and may help you gain some clarity into the type of changes you want to make (either in the comfort layers for pressure relief or the support layers for alignment).
Combination stomach/side sleeping is by far the most difficult, risky, and most challenging sleeping combination of all because the needs of stomach sleeping are completely opposite to the needs of side sleeping. It’s important to have “just barely enough” thickness and softness in the comfort layers of the mattress to provide good pressure relief on your side and no more than that along with a “firm enough” support core (especially under the pelvis which is the heaviest part of your body) so that you are as close as possible to the firmer support in the mattress to help keep you in alignment when you sleep on your stomach. A firmer middle zone or even a belly band (a layer in the middle of your mattress) can also help with this if that’s an option that is available because it can allow for thicker or softer layers under your shoulders with less risk to alignment when you are sleeping on your stomach because a firmer middle zone can “stop” your heavier pelvis from sinking in as far and sleeping in a swayback position. The biggest issue for side sleepers is generally pressure relief and the biggest issue for stomach sleepers is generally alignment because of the tendency for the hips and pelvis to sag into the mattress and a firmer center zone and softer shoulder zone can sometimes help with both.
Other than this … I think that the most effective suggestion I could make is now that you have some experience sleeping on your mattress and the “symptoms” you are experiencing you may be in a much better position to go back to the showroom and evaluate the differences between your mattress and the other options that they have available using the testing guidelines (making sure that you spent at least 15 minutes on every mattress you are considering after you have reached a “pre-sleep” state of complete relaxation). I would make sure that you “listen” very carefully for the more subtle cues from your body for any hint of “familiarity” or any of the early signs of the “symptoms” you are currently experiencing and that you hope to change.
The change in coil firmness certainly makes sense for stomach sleeping and the lower back pain but I would have stopped there to see how it affected you because it’s also not surprising that changing your comfort layer at the same time to a firm would would make your pressure issues worse on your side. This double change in firmness may have “jumped over” the combination that would have worked best for you or at least made it more difficult to assess what to do next because by changing both the support core and the comfort layer of the mattress at the same time it can make it much more difficult to decide which change in which layer or component did what. I would keep in mind that comfort layers and support layers each have different functions and while they interact together and affect each other … one is more responsible for “allowing” your pressure points to sink in more and providing good pressure relief and the other is more responsible for “stopping” the heavier pelvis from sinking in too far and sleeping out of alignment.
It’s also possible that “allowing” your upper body to sink in more with a softer comfort layer on your firmer innerspring may help your alignment as well because you may be sinking in more evenly with your upper body and it would certainly help with pressure relief.
I would also test the combination that your husband was sleeping on which is the softer innerspring with firmer comfort layers.
If neither of these prove to work well for you then the next logical step would be firmer support yet to prevent your pelvis from sagging or middle zoning and you would need to talk with them about these or any other options they have available. Once you have the alignment you need then you can build “comfort” and pressure relief on top of this. It’s also possible that switching to natural Dunlop may be worth testing as well because it has a higher compression modulus which means it becomes firmer more quickly as you sink into it more deeply than the synthetic so it may work for pressure relief because of its initial softness and point elasticity (ability to contour to your body shape) but also be more supportive because of it’s ability to resist deeper compression more effectively.
It’s also possible that a change in pillow may help “enough” with any pressure issues on your shoulder so you can focus more on alignment . Stomach sleepers need a thinner pillow but this may be too thin for side sleeping so a pillow that can be “scrunched” may be worth considering so you can have the thinner pillow you would need when you sleep on your stomach but can fluff it up when you sleep on your side to keep your head and neck in alignment and take some of the pressure off your shoulders.
So overall if I was in your shoes … I would go back to the showroom and test the softer latex over the firmer coils to see if this provides a better combination of pressure relief and alignment in all your sleeping positions and I would also test the softer coils with a firmer comfort layer and test the natural Dunlop to see which of these possibilities appears to work best for you and if none of these appear to be effective I would talk with them about what other options you would have.
Hopefully this will give you some reference points that you can test to confirm which of the guesses or “theory” will work for you in real life.
Phoenix