My existing mattress is 11 years old and I have been very satisfied with it, and need to replace it.The details on my existing mattress label are as follow:Kaymed Pocket Visco 1600 5' bed soft support1600 hand-nested pocketed springs in double size with 6 cm layer of V8 5S visco elasticcushioning for luxurious sleeping comfort .I am 5'7" x 13 stone my wife is 4'11" and 11 stone 5lb.With the existing mattress we do not roll together.What is your comparable replacement please?Thank you Regards Roger Bellamy