I bought the mattress for the guest room. I slept in it a couple of nights. It seems pretty comfortable. Just had first guests this weekend. They seemed to like the mattress too.
I am very happy with my new mattress. It has sufficient support for I bought it because my old, worn traditional mattress was causing me to wake up with back aches), and it was quick and easy to get and set up. I like all foam (or similar) material mattresses such as this one. The only reason for a 9 instead of 10 is to take into account that some people may prefer or require a mattress of different construction.