Purchased this mattress a couple months ago for guest bedroom.  Used 1x last week and something about the height of  mattress seemed funny.  Measured it…head and foot ends of mattress only expanded to 9”.  Measured sides and only in one area did it measure 12”—other areas between 10 and 11”.  They did say it slept comfortably, but expansion for a 12” mattress is way off.