Hi, I am looking to buy a new mattress. I weigh just under 10 stone. I have always had a medium tension which has always been suitable. I have now tried some medium feel mattresses and they feel quite hard. I do get backache at times so would ideally like a very comfortable mattress for my size. The last mattress I bought had innergetic latex which was very comfortable but lately, it certainly isn't. I have had this mattress for a few years now. Any comments from you would be greatly appreciated. Thank you.