I am 70yrs old, 5ft and 11 stone and need to find a VERY comfortable mattress for my 4ft bedstead. At the moment I have a Vispring Imperial soft mattress which I find so uncomfortable I have taken to sleeping in my spare room! Apart from a softer margin the rest of the mattress seems to have compressed to a solid mass which is incredibly uncomfortable. It is even difficult getting out of the bed as you seem to get stuck in the dip in the middle. I have the option of exchanging this for a medium firm mattress but feel that this may be even worse so I may have to purchase a totally new product and lose my £2000! I am very impressed with your informative website and, should I need to buy a new mattress, may well come to you. I would expect the product to last my lifetime so need to make an informed decision. Many thanks.