Wayfair Sleep 13.5-Inch Medium Cooling Gel Memory Foam Mattress for $280: This 13.5-inch cooling gel memory foam mattress is listed as medium-firm, but is by far the most plush mattress I’ve ever slept on. Wayfair Sleep 14-Inch Plush Cooling Gel Hybrid Mattress for $340: This 14-inch plush cooling gel mattress feels expensive without the price tag to match. Wayfair Sleep 14-Inch Medium Memory Foam Mattress for $290: This 14-inch medium-firm memory foam mattress strikes a great balance with structured firmness and a memory foam top that contorts to your shape. Although I tend to go for more plush mattresses, it has a great balance between that medium-firm structure and the soft, contorting open-cell memory foam. Next Up AccordionItemContainerButton LargeChevron I'm testing the Zinus 12-Inch Green Tea Memory Foam Mattress.