Hi, I think no one answered your post because you did not give enough info.
We need to know how heavy you are - your height and weight matters.
If you are 5 feet 2" and weigh 110 lb then I'd say 3" of the right kind of latex might be okay for you, though honestly I doubt it.
I weigh about 190 and am 5'10" tall and I am sleeping on about 4" of latex. From the top down:
*1" of Natural Talalay - 32 ILD
*1" of Talalay, maybe Talatech, not sure - around 28-34 ILD.
*about 2" of firm Dunlop (it's supposed to be 32 ILD but it feels more like 36 or 38ILD to me.
A frame like this from IKEA except mine does not have the 5 zones, mine is the same top to bottom, but bowed wood like this. I could not find it at IKEA's site, I think they no longer carry it:
http://www.ikea.com/us/en/catalog/products/60125969
I cannot tell you how many different springs and layers of latex and memory foam I tried before hitting on this. Some of the long-time forum members here can attest to that! ;-D
I tried latex and memory foam combinations, I tried latex only, memory foam only. I tried it with wool toppers and with Omalon toppers. I tried latex and/or memory foam over different kinds of springs.
In the end I found: Less is more. 4" of Dunlop and Talalay over bowed wood is the best thing I have found!