I have a 196 cm x 180 cm Millbrook 2500 spring mattress and base at the moment. I'm looking to change the mattress shortly but keep to the same sized bed base. I am around 17 stone and a have a rather large posterior, which bows my back causing lower back pain if the mattress is to hard. I am also a very warm sleeper, so like a cool bed. I was looking at a memory foam type mattress but think it will be to hot but I like the body cradling/supporting nature of memory foam. Could you suggest a range of mattresses that would suit me? Many thanks.