J.K.
I've never had either, but I do know that the temperpedic is full of chemicals and off gases a lot. So if you are chemical sensitive, do some research on that. I had a temperpedic pillow probably 15 year ago, and after 5 or so years, it started to separate into two pieces. I know someone else who had the same problem. The technology could very well be much better at this point. Read the fine print on the warranty very carefully.
I know two couples with the sleep number bed. One couple has the dual chambers so that each person can have their own setting; the thing that sucks about that one, is that there is a hard part between the two of you so you can't cuddle easily. I would HATE that.