Is the OBUS FORME that is on sale at Sears memory foam, or just regular foam? If it's memory foam, just know that it's not the same thing as regular old foam. For me, I would only want to use memory foam as a topper (actually, I don't really like it at all, but I could see its use as a topper).
Others may like it as a mattress, but I'm just mentioning it so that you can investigate further.
When you are looking at regular foam, things to keep in mind are the density and the ILD number. This gives you standardized information about how dense and how "firm" the foam is. If you go to a website like www.foamsweetfoam.com
, you can learn more about this (they keep it simple and to the point):
There are many properties of foam. The two most important are: Density and ILD.
Density is nothing more than how much a piece of foam weighs. It is determined by taking a cubic foot of foam (12" x 12" x 12") and weighing it. If the foam cube weighs 5 pounds, the density is 5.0. If it weighs 2.5 pounds, the density is 2.5. The higher the density, the longer the foam should last. The best foams for extended use are ones with a density of 1.8 or higher. Foams with a density of less than 1.8 are adequate for temporary use.
ILD stands for Indentation Load Deflection and refers to the firmness of a piece of foam. The lab puts a 4" x 15" x 15" piece of foam on a flat surface. Then a round metal plate, 8" in diameter, pushes down on that piece of foam. The amount of pounds of pressure it takes to squeeze the 4" piece of foam to 3 inches (25% compression) is referred to as the ILD. A low ILD, such as 10, doesn't offer much resistance and is an extremely soft piece of foam. A piece of foam that takes 46 pounds of pressure is an extra firm piece of foam. Generally speaking, ILD's of 10-22 are considered soft, 23-29 are medium, 30-37 are firm, and 38+ are considered extra firm. The comfort range for most people is 25-35. Foam does soften slightly with regular use.
(I bought regular foam from them a couople of years ago; now it looks like they only sell latex foam, but their ILD and density info is still appropo.)