Mattresses recommended for adjustable beds

Hi.
I have been looking through the various web sites for 2 new single mattresses for our adjustable bed because the the ones in use are pretty well shot. I've come across your site and found it very informative not only with your products but the the write ups on the various elements that make up a mattress. Being an older person I've found it easy to read and honest with it. My wife suffers from arthritis and other related problems so I must make sure that I pick the mattress that compromise her condition. I am relatively free of aches and pains. My wife's weight is about 11 stone and mine is around 14. Any advise that you can help me with on selection would be useful to me.