Bought this mattress coz had a bad back for years, my previous mattress was a firm posturepedic and I woke early every morning with a painful lower back, I didn't/couldn't have a lie in for years!
This mattress is not a miracle cure, I still get pains (probably just getting old) and I honestly think the trial period should be 3 months coz that's how long it takes for your body to get used to a new mattress,  that being said, I love it , it's so comfortable, I feel like I sleep better and I can have the occasional lie in ... woo hoo!