I got my son one of the kids mattresses several years ago and loved the feel and the cooling effect it had so I finally decided to get a purple matress to put on my adjustable base. Because we have a split king the mattess had to be a twin XL so I could not buy the kids one for me. It does seem firmer and less cooling, but since I've started sleeping with the zero gravity setting I've noticed I feel more comfortable but still wake up hot. I may have to try the similar sheets as I didn't really like the super stretchy ones I got for my son, however I'm thinking that might be part of the cooling factor that the semi-stretchy split king sheets with cotton flat sheet do not have.