Sleep Master - 8

According to the Amazon listing, it's just 3 layers of dense foam with a cotton cover. The story is interesting but the only selling point seems to be the return policy. You can get more mattress for less money from Ikea or even Amazon itself, and I wouldn't want to sleep on 5 inches of foam at any price -- it's more a mat than a mattress, and is going to be even thinner once you put your body weight on it.

Their twin is $199, and less than half the height of a normal mattress. For $139 you can get a 5-star-rated 8" foam mattress with 4" of dense foam, 2" of soft foam and 2" of memory foam, delivered tomorrow with the same certifications and 5-year warranty. [1] For $229, you can get a 12" foam mattress, which is more like a traditional full height mattress. [2]

1: http://www.amazon.com/gp/product/B006L9QN4G/ref=oh_details_o...

2: http://www.amazon.com/Signature-Sleep-12-Inch-Memory-Mattres...