I went ahead and took the stock mattress off and pulled out the foam (easy job). I cut away the thin 1 inch blue stock soft gel and added a 2 inch gel top in the mattress case (hard job) with the stock 4 inch foam. With sheets off, it looks stock but feels 1000% better. I use Beddys all in one sheets and blankets. Amazing difference. The murphy bed mattress is a really odd size, so options are limited.