Hello, after much trying out of mattresses in John Lewis and also comparing the feel of them when putting them on the floor, I have concluded that a sprung base actually makes a huge difference in terms of comfort and getting that 5 star hotel type feel. Therefore I am very much in favour of trying to replicate that feel, but the issue is that I am in a rented apartment which has a non sprung divan and there is not space to store it somewhere to buy a sprung replacement in its place. So I am now trying to find something suitable that can go on top of my firm divan to replicate a sprung divan. The closest thing I can find on the web is a thin Harrison 'under mattress', but that is all I can find which tries to achieve this goal. Do you have any other recommendations to achieve such a goal? The other thought I had was buying a topper with equivalent properties, but then there are lots to choose from and its hard to know what type and firmness will give a similar feel. Many thanks for any advice or recommendations.