Beautyrest World Class™ Level Four Medium 15 inch Mattress

I chose the World Class over a hybrid specifically because I preferred the feel, but the 15-inch depth means more comfort layer insulation than thinner mattresses. It sleeps warmer than I expected. If you're a hot sleeper and want this mattress, invest in a cooling mattress pad or moisture-wicking sheets to compensate. The medium feel and support are excellent — just not as cool as I'd hoped.

I have positional sleep apnea — worse when sleeping on my back. My sleep therapist recommended medium firmness to make side sleeping comfortable enough to stay in position through the night. The 15-inch depth with its thick comfort layers makes side sleeping genuinely comfortable for me. My nightly positional data from my sleep tracker shows I'm spending significantly more time on my side. My AHI has improved noticeably as a result.

Zero detectable odor when we unboxed it. The mattress expanded fully within about two hours and we slept on it that same evening. First night was immediately comfortable — no break-in stiffness, no unfamiliar feel. Just excellent medium support from hour one. Outstanding experience from unboxing through every night since.

My biggest concern with a 15-inch mattress was heat retention — more layers should mean more trapped heat. The Beautyrest engineers clearly addressed this: the pocketed coil system creates significant airflow through the core even with the additional comfort layers above it. I'm a hot sleeper who has been sleeping without overheating on this mattress consistently for five months. The 15-inch depth does not compromise the cooling performance.

At 15 inches thick this Beautyrest World Class Level Four is the deepest mattress I've owned and every inch justifies itself. The medium feel is perfectly calibrated — you feel the support of the coil system working beneath comfortable layers that cushion without compressing. It doesn't feel like a thick mattress trying to be comfortable; it feels like a mattress engineered to be exactly this deep. Four months in and I've never slept better.