For a few weeks now I have been sleeping with a FlowSleeping System (plates; mattress & pillow made of natural rubber). This has improved a lot in terms of my sleep quality! The back pain when getting up has disappeared and arms falling asleep lying on your side are a thing of the past. So lounging can be so comfortable. Joy prevails! It all began with detailed advice on lying and sleeping, followed by professional product information.  Delivery & installation as well as the subsequent removal of unused material went perfectly.  I'm very satisfied.