I have owned the 5.5 inch mattress topper for a little over a month now and let me just say OMG!!!!!!! I have a very firm mattress that was given to me and was waking up every morning with severe back and neck pain. After about a week of sleeping on this it is GONE and I am waking up SO rested!!! I only hate that I waited so long to buy it!! Other reviewers have mentioned that it is hot and it does cause a little extra heat but it is def not a big deal. I am VERY hot natured and the extra heat is def not a big deal considering that I am getting the best sleep I have had in years!!! If you are thinking anout this topper, stop it and but it! You will not regret it, if I could give it higher that a 5 I most def would!!!