I purchased this because it was described as being 5" thick and with a measure mark showing the thickness of the mattress topper. When this arrived I could see that this did not look to be 5" so I measured it and found it to be only 3" thick. I did not make a mistake on the one I purchased as this was the only one that was advertised. There is no way that this could measure 5" in depth so if you are thinking of purchasing one of these keep this in mind. If I had known this before I purchased it I would not have done so. I did decide to keep my mattress topper because of the cost of returning it, etc. As for the topper itself, it does make a difference, although not as much as a proper 5" one would. It does need to be shaken a few times a week at least. Would I recommend this? No, purely because you do not get the 5" thickness that is advertised. Surely, trades description comes into this somewhere.