I regret buying the medium firm because it's too "mushy" for my liking. So many reviewers mentioned it may be too firm but I guess it depends on what your definition is. To me, at 200 lbs, I don't like sinking in 5 inches. Not only is it not comfortable for me, but it's SO HOT!! I'm boiling at night. I tried so many toppers already, cotton blankets, etc. and nothing is keeping me cool. My AC is blasted low and still. The foam toasts you. I'm going to try a wool blanket under my sheet as I read that wool wicks away heat. Will see. I wish I could just return the mattress but it's just not doable. The thing, once expanded is very heavy (heavier than a normal mattress) and unpack-able. C'est la vie. :(