Hi. We currently have a Sealy cascade posturepedic 2000 pocket sprung double mattress. It has had its life now but we have loved this mattress as we get on with the firm support of it. We are interseted in your Origin Pocket 1500 or 2000 king size mattress which fits our budget. I am 11 stone and my wife is 10 stone and I know you recomend the Origins 1500 medium support for our weight, although as I say we are used to a firmer support. What would you advise us to go for? Is the 1500 on the softer or firmer side of medium and how firm is the 2000? Many thanks. Dan