Hi Overcomer,
If the current problems with your mattress or “sleeping system” are connected to a sagging foundation … then replacing the foundation would help. If they are connected to low quality materials in your mattress that have softened … then it will help little if at all. Post #2 here will give you a good idea of which types of foundations or box springs generally (but not always) do best with different types of mattresses but if a different type improves your sleeping experience then there isn’t a “rule” that says that only one specific type should be used with any particular mattress (unless of course it is part of a warranty condition and maintaining the warranty coverage is an important consideration).
One way to tell is to put your mattress on the floor and see what if any difference it makes. A firm non flex foundation will perform in a similar way to the floor. Post #4 here may also give you some useful information about mattress sagging.
Their mattresses will almost always be set up on an “active” box spring and if you want to test them to see the difference between this and a firm non flex foundation … you would need to ask them to put it on either this type or an adjustable bed (which has a rigid base).
I did a quick scan of your area around Claxton and some of the better local possibilities that may be worth including in your research on a “mattress by mattress” basis and the brands they carry I would focus on (assuming that they can provide you with the specifics of what is inside them) include …
Master Bedroom Furniture Claxton, GA. Englander (make latex and memory foam)
http://www.denmarksfurnituremart.com/our-brands/index.html Brooklet, GA. Restmaster (lower end of the budget range) and Englander (made by Spears) latex hybrid and memory foam models.
http://www.dealsfurnitureofstatesboro.com/ Statesboro, GA. Corsicana, Restmaster, They were not very knowledgeable about what they had on the floor but both Restmaster and Corsicana can be better value in the lower budget ranges (assuming you are able to find out the specifics of what is inside them which may be difficult in the case of Corsicana). No latex.
http://www.lariscyfurniture.com/mattress.aspx Sylvania, GA. Therapedic.
http://www.gibsonshomestore.com/ Hinesville, GA. Symbol.
In addition to these …
Post #2 here includes some of the better options and possibilities I’m aware of in the Savannah, Hilton Head Island, and Charleston area.
Post #10 here includes a few possibilities in the Douglas/Waycross, GA area.
Post #7 here includes the better options I’m aware of in the Jacksonville, FL area.
And post #2 here (which you may have seen) has some of the better options in the Atlanta area.
Of course the better online outlets such as those in post #21 here (who are the members of the site which specialize in online or “on the phone” purchases and guidance) can also be a great source of value and can also be a reference point for value locally as well.
Hope this helps
Phoenix