Hi Jmadden18,
While it’s also not possible to quantify the sleeping temperature of a mattress for any particular person with any real accuracy because there are so many variables involved including the type of mattress protector and the sheets and bedding that you use (which in many cases can have just as significant an effect on sleeping temperature as the type of foam in a mattress) and on where you are in the “oven to iceberg” range and because there is no standardized testing for temperature regulation with different combinations of materials … there is more about the many variables that can affect the sleeping temperature of a mattress or sleeping system in post #2 here that can help you choose the types of materials and components that are most likely to keep you in a comfortable temperature range.
Latex in general is the most temperature neutral of all the different foam materials and memory foam is generally the warmest although there are many versions of every type of foam (latex foam, memory foam, polyfoam) that can vary in their breathability and temperature regulating properties. There is more about the general differences between latex and memory foam in post #2 here.
In very general terms … the materials, layers, and components of a sleeping system that are closer to your skin will have a bigger effect on airflow, moisture transport, and temperature regulation than materials, layers, and components that are further away from your skin and softer mattresses will tend to be more “insulating” and for some people can sleep warmer than firmer mattresses. Memory foam in general (with or without gel) also tends to sleep warmer for some people than other types of foam and while thermal conductive materials (such as some types of gel or copper) or phase change materials that are infused in the memory foam will generally make a mattress feel cooler when you touch it and can provide a temporary benefit when you first go to sleep at night … once temperatures equalize the temperature regulating benefits don’t tend to last over the course of the night. There is more about some of the ways that different manufacturers are using to cool down memory foam in post #6 here and while it would generally only involve a minority of people … it would be fair to say that there are a larger percentage of people that tend to sleep warmer on mattresses that use memory foam or even gel memory foam in the top layers than other types of more breathable and more temperature neutral foam or fiber materials.
In the end though … outside of these very general guidelines which will let you “play the odds” a little more effectively … the only way to know for certain whether a mattress will be “temperature regulating enough” with the sheets and bedding and mattress protector that you use will be based on your own personal experience because there are always some people tend to sleep warmer on mattresses that most people would be fine with.
Phoenix