Which mattress would you recommend?

I am putting this out to you, my friends, and please: I need your input on this. It is quite a serious issue, because if you wake up every morning with back pain, it is no longer funny! We have had this "very good" mattress (I won't mention names due to possible lawsuits), for two years, they came out to assess it, and said it falls within the SABS standards for it's age! Well, I don't want to sleep in my bed... we have previously had another mattress by the same company, as it is a reputable mattress, and the same thing happened after 5 years. So now I am asking you, if you have had a mattress for 10 years and it is still going strong, please let me have it's name. You can mail me to mziman@vodamail.co.za if you do not want to publish your reply here. Please help!