Hi mike7,
If I call Diamond Mattress what are the questions I should ask.
In a perfect world the retailer that sells the mattress should be able to tell you the specifics of what is inside it and if they don't know they should be the ones calling the factory to find out.
If for some reason they aren't willing to find out the information you need and you are determined to find out yourself then you would have no alternative but to call the factory yourself and find out the specifics of the mattress you are considering (including the thickness of all the layers, the density of any polyfoam or memory foam, the type and blend of any latex, and any information about any innersprings in the mattress and the quilting and cover that you are able to find out).
To summarize.
Latex and Memory and all Foams have heat issues. Those with wool tend to sleep cooler. Yet those like the Pure Bliss Latex mattress that use a stretch knit cotton wont dissipate heat and thus a wool protector or pad would help however there isnt a wool protector that doesnt change the feel of latex except the st dormier which has a terrycloth feel under the sheets.
For most people memory foam, polyfoam, and latex don't have heat issues but depending on the specifics of the mattress for some people they do. Heat issues with memory foam (especially thicker layers) are more common than with other types of foam and of the three types of foam materials that are normally found in mattresses latex would generally have the least amount of heat issues because it's more breathable than most other types of foam.
Natural fiber / innerspring mattresses with no foam at all are the most temperature regulating of all the mattress types but they can also be very costly and many are in the "ultra premium" range
Some people prefer the feel of a quilting layer over memory foam or latex (natural or synthetic fibers or foam) and some people prefer more of the feel of sleeping directly on memory foam or latex itself. Thicker less stretchy mattress protectors and mattress pads will have a larger effect on the feel of the mattress than thinner more stretchy materials. The St Dormeir will also have some effect on the "feel" of the mattress but it has less wool than other similar mattress protectors and is a little more stretchy so it will have "less" effect than others of the same type.
Phoenix