Was a little worried when I saw how tightly rolled the mattress was on arrival but, the moment I unpacked it, it fell completely flat and started to expand (It had been vacuum sealed).  I'm 7 months pregnant and find it hard to get comfy at the moment, but I jumped (ok, flopped) on to test it and was pleasantly surprised at how supportive and comfortable it was.  I could even lean on the edges to get back up again (no easy feat for me right now), recalling as I did that the mattress boasted reinforced edges.  For the price, it's an excellent little mattress and you shouldn't be put off at the thinness of it (I bought it specifically for a trundle under bed) as I believe it will provide the odd comfy night for an adult and many comfy nights for a young child.  Very pleased.