Hi Premalata,
The Briella uses the Tempurpedic Cloud Luxe as a reference and the Lux uses the Tempurpedic Grandbed so I would use that as your guideline (which of the two Tempurpedics is the best match for you in terms of PPP) along with a more detailed discussion with them on the phone and the other parts of your personal value equation that are most important to you to help you decide which one out of these two would be best for you.
Phoenix