Hi sleeplessinutah,
Thanks for taking the time to share your comments and experiences … I appreciate it.
As you probably know from your reading here … adding a topper to improve the comfort or pressure relief of a mattress that uses lower quality and less durable materials is often just a partial or temporary fix because if the lower quality materials start to soften or sag prematurely then the topper will just “follow” the soft spots or sagging in the mattress. I would also be very cautious about adding 4" of memory foam to any mattress because for most people in your weight range it would have a significant risk of being too soft to provide suitable support/alignment.
As you probably now from your reading here as well … there are no “standard” definitions or consensus of opinions for firmness ratings and different manufacturers can rate their mattresses very differently than others so a mattress that one manufacturer rates as being a specific firmness could be rated very differently by another manufacturer. More importantly though … different people can also have very different perceptions of firmness and softness compared to others as well and a mattress that feels firm for one person can feel like “medium” for someone else or even “soft” for someone else (or vice versa) depending on their body type, sleeping style, physiology, their frame of reference based on what they are used to, and their individual sensitivity and perceptions. There are also different types of firmness and softness that different people may be sensitive to that can affect how they “rate” a mattress as well (see post #15 here) so different people can also have very different opinions on how two mattresses compare in terms of firmness as well and some people may rate one mattress as being firmer than another and someone else may rate them the other way around. This is all relative and very subjective and is as much an art as a science.
There are some suggestions in post #2 here and in post #3 here that may be helpful if your mattress is too firm but the first thing I would suggest before making any changes to your sleeping system is to give your mattress more time so that the mattress has a chance to break in a little more and your body has the chance to get used to a sleeping system that is very different from what it’s used to sleeping on.
Foam materials will soften over time and not get firmer so the initial break in and adjustment period over can work to your advantage.
The biggest issues with using other people’s experience on a mattress as a guideline for your own isn’t inconsistencies in the firmness of the foam materials or the mattress “as a whole” but just differences in how different people perceive softness and firmness (see my previous comments). This is why you see so many reviews that are all over the map in terms of how the firmness of a specific mattress is described by different people. In the case of memory foam then the temperature or humidity of the sleeping environment or the layers or fabrics that are on top of the memory foam that affect how much body heat reaches the memory foam can also make a difference in the firmness of the memory foam although this wouldn’t apply to the latex in your mattress since it isn’t temperature sensitive.
There is 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.
If none of the suggestions in the posts I linked help and your mattress is still too firm for your specific needs or preferences after a few more weeks then you have some good options available to you. Brooklyn Bedding has a great return/refund policy that makes it easy to test a mattress in your bedroom instead of a showroom so there is little risk in trying it. You could either return it and choose a different mattress or exchange it for the softer version.
You could also add a different topper that would be a more suitable choice than your 4" memory foam topper to provide any additional comfort and pressure relief that you may need. If you decide to go in this direction then post #2 here and the topper guidelines it links to can help you use your sleeping experience as a reference point and guideline to help you choose the type, thickness, and firmness for a topper that has the least possible risk and the best chance for success and also includes a link to a list of some of the better online sources for toppers I’m aware of as well (including Brooklyn Bedding/Dreamfoam).
You certainly made a great quality and durable choice but of course comfort and PPP and how well you sleep on a mattress is the most important part of the “value” of a mattress purchase so it’s good to see that you had the foresight to choose a mattress where you have some great options available after a purchase just in case your experience doesn’t turn out as well as you hoped for.
Phoenix