HiI am 5ft 5 and 65kg, I sleep alone (apart from the cat!) and I would like a new latex mattress, ideally to put on my existing slatted base whose slats have a 12cm gap between them. I like a bed with a gap underneath to use for storage, and so the cat can hide under there....My current pocket sprung mattress is around 10 years old but I am suddenly getting a stiff neck and shoulders/hips in the morning after sleeping on it. I am mainly a back sleeper. I used to think I liked a firm mattress, but now I'm getting older (42) I'm not so sure.I am looking at your latex range, and I am not sure which would be best for me - the origins or the fusion?Thanks Emily