Follow-Up: I have been sleeping on a Select Comfort mattress for awhile now, and it has helped my sore back immensely. My Sister-in-law has fibromyalgia so I recommended it to her and she has now been sleeping on hers for over a month. It is helping. The Select Comfort mattresses are adjustable, so you can have it as soft or as firm as you would like it. It gives you even support and relieves your pressure points. Along with a good pillow,you really have no pressure points. I recommend you try one. They are phenomenal!!!
Here is a link that might be useful: Select Comfort