As a former Olympic weightlifter and lifelong athlete, my shoulders and low back have taken a beating. My old mattress was causing low back pain and hurt my shoulders when I would sleep on my side. I decided to try the Sealy Performance Hybrid based on reviews I read after literally reading and searching for a mattress for two months. I read about mattresses in a box, innerspring, hybrid and every other mattress including futons and waterbeds (didn't even know they still made these!). After much research I decided on the Sealy Performance Hybrid and I cannot begin to say enough good about it. The very first night I slept on it I was out like a rock and got incredible sleep. I track my sleep patterns using a watch the records ANS (Autonomic Nervous System) and sleep cycles. Every reading went to the "Very Good" range and it hasn't stopped. This is by far the best mattress I have ever owned and if I could give it 10 Stars, I would! Buy it and sleep great!