I'm 10.5 stone and a side sleeper. My current mattress is a medium pocket sprung with memory foam topper. After about 5 years, I started getting lower back pain. Moving to different parts of the bed helps, but after a week or so I get uncomfortable again, as the memory foam is too saggy. My back tends to do better on a firm mattress, but then I get sore hips!! I ended up ordering a medium pocket sprung mattress with memory foam from a shop today, as was assured that the technology has improved. However, I've seen some online reviews suggesting that I may end up with the same problem. I'm thinking of phoning the store tomorrow to change it to a more expensive medium firm pocket sprung, 1600 coils, no foam. It felt ok in the shop, but I was nervous about my hips. If I get it and my hips struggle, would a topper solve the problem?