10-Year Tested Mattress Topper: Surprising Cooling for Side Sleepers When it comes to finding the perfect mattress topper for side sleepers, the promise of cooling technology often feels like a marketing mirage-until you encounter the COONP line, which has been rigorously tested over a decade to deliver unexpected relief. Take the COONP Queen, King, and Full Mattress Topper, for instance: each boasts an extra-thick pillowtop design, a cooling plush pad cover made from cotton, and a deep pocket (8-21 inches) engineered to adapt to various mattress depths. These toppers blend comfort with breathability, offering a soft yet supportive layer that seems to defy traditional expectations of warmth. But not all cooling solutions are created equal. The SyMax Cooling Mattress Topper steps in with high-density gel memory foam, a 4-inch thick cushion that swallows heat and leaves the bed feeling like a freshly aired room. Certified for safety by CertiPUR-US, it's a firm favorite for those seeking pressure relief without sacrificing temperature control. Meanwhile, the 3-inch Gel Memory Foam Mattress Topper Queen offers a more minimalist approach, its compact profile ideal for light contouring and quick cooling, though it may not provide the same level of plushness as the COONP options. The true standout? A marriage of durability and innovation. While the COONP toppers prioritize a cozy, layered feel, the SyMax model leans into advanced foam technology. Both lines, however, share a common thread: they've stood the test of time, proving that cooling for side sleepers isn't just about gimmicks-it's about thoughtful design. Whether you're prioritizing all-day plush comfort or a precise temperature balance, these toppers redefine what it means to sleep soundly.