OH - MY GOODNESS!!! These mattresses reached their full potential in just 48 hours! I have never experienced a product that hits every checkbox, especially not a mattress. Not only is it great for my back, but it had no smell like my previous foam mattress - and it's the HIGHEST AULITY I have seen for that price range. I would HIGHLY recommend purchasing from THIS company, and these mattresses are incredible! The best sleep I've gotten in four years!