I'm in the market for a King size bed (divan/ottoman). My budget is around 1200 but I'm having difficulty in determing an appropriate matress after lying on a few at retail stores. I've tried both the medium soft thermapur serenity which I instantly liked the feeling of best and also the memory foam sensaform 9000 but I don't what would be best suited. I'm also a bit concerned about memory foam causing me aches and pain due to sag and compressing too much due to a soft spring despite liking the softer feel. I'm a traditional side sleeper, sleeping on my left side and generally do not move from that position. My weight is approximately 60kg and I'm 6ft tall. I have looked at range of matresses from latex and pocket sprung, combination matresses and also hypnos matresses. I am tempted to purchase the thermapur serenity as everything else I tried didn't come close apart from the sensaform 9000. What spring tension matress will best support me and what upholstery layers should I be looking for in a matress given my budget? I need some clarity to aid my decision making process as I'm getting confused as to exactly what the best bed/matress I can get given my budget, what would you recommend?