Hi lotus65,
I certainly understand and there are many who feel the same way. While your own personal testing and experience is always a more accurate way to “predict” your real life sleeping experience than any “theory at a distance”, there will always be cases where your testing doesn’t seem to match how you feel when you sleep on the mattress for a while and if you are one of these and don’t have any real confidence in your testing or are unsure about how well a mattress will work for you then an exchange or return policy or any options you have available to fine tune the mattress after a purchase (along with the costs involved and having good options available for an exchange) would be your “backup plan” and in this case it would probably be one of the more important parts of your personal value equation.
Phoenix