After reading the reviews I thought I would get the most comfortable mattress ever. I was wrong. I first ordered the Perfect Sleeper Renewed Sleep pillow top firm. All the talk on the description about pressure-relieving comfort and support with the special layers. It just felt like a very firm mattress - no give. I exchanged for the Luminous sleep 3-layers of comfort without the pillowtop thinking maybe the pillowtop was infringing on all that pressure relieving comfort and the medium firmness. I was wrong again. I did not feel any pressure relief comfort, still feels very firm even thought the firmness is "medium" and no cooling effect noticed. Basically, it is a good mattress. Nothing special. It is no more comfortable than my old firm pillowtop by Beautyrest. It is also not clear that the 120-day trial only applies to the first mattress you buy. If you exchange it, you get what you get. Serta is obviously a good quality brand. Just note, the whole pressure relief comfort is not there, at least in the two I received. I personally do not feel it was worth the money. Perhaps the plush firmness would be different, but I can no longer exchange.