Hi Keepcooler,
[quote]Amerisleep Liberty Bed - uses BioH plant based soy foam that Cargill says sleeps cooler (but the company has an F rating from BBB:()
Bed In A Box - Tranquility Gel - their “coolest sleeping mattress”[/quote]
You can read a little more about Amerisleep and Bedinabox in the links in post #2 here. You can also read more about so called “plant based foams” in post #2 here. The plant based foams are more about marketing than any difference in quality although they can be a “small step” in the use of more sustainable materials.
Outlast is a phase change material which means that it can regulate temperature to some degree in both directions (cooling and warming). Like other materials or fabrics (such as coolmax fabrics, fabrics that use natural fibers such as cotton, viscose/rayon fabrics, or wool in a quilting layer as just a few examples), it can make a difference in sleeping temperature but how hot you sleep on any specific mattress will depend on all the other factors that in combination with each other can affect sleeping temperature … not just one. Some people will tell you that a mattress that used Outlast (either in the cover or the top foam materials) worked very well for them in terms of temperature regulation while others may tell you that they still slept warm on a mattress that also used Outlast but it would certainly be one factor that in combination with others can make a difference in regulating sleeping temperature and help offset the tendency of memory foam to sleep warmer than other materials.
Phoenix