Shetland pocket V's Tempur?

Without knowledge I am drawn to the idea of a Shetland pocket spring level 1 comfort mattress. My present mattress is 11 years old on a Slumberland 4 drawer divan base. I have multiple degenerative conditions and am an octigenarian. I am awaiting heart valve surgery. I would love to have a really comfortable lie. My weight is just under 11 stone. Have you any comments?

In my small bedroom I have a Single Tempur multifunction base and mattress which I do not love and therefore avoid, in favour of the 4.6" size Slumberland, as above.