My wife and I are looking to buy a new mattress. We are both tall (I am 6'7" and my wife is 5'11") and normal weight (I am ~15st, I do not generally ask my wife her weight...). I am looking for a more comfortable nights sleep and currently think that my mattress is to firm or is not allowing me to attain a correct sleeping 'posture' (spine alignment?). I have tried a few mattresses briefly in a shop and liked the concept and feel of the combination type mattress (pocket springs with softer memory foam/other padding layer on top) rather than purely pocket sprung or entirely memory foam. However, I am someone that generally feels 20 degrees warmer than my wife and am concerned by things I have read where people find memory foam etc very warm. We are pretty flexible on budget as long as we get a mattress that works for us. Any advice is welcome.