We bought a superking una mattress - it's organic (GOTS and GOLS certified) and it comes with 3 layers per side (a tolla of 6 layers) which allows you to customize the hardness. We were mainly looking for an organic mattress. At first, it seemed like the fact that the mattress is of customize-able hardness is not too important. However, given I weight about 90kg and my partner is about 60kg it was really useful to have a customize-able mattress. On my side, even the hardest configuration felt like being too soft, but my problem was solve really nicely. I have spoken to customer service online and got to replace the soft layer for a firm layer (for free) with which I have managed to achieve a perfect hardness for me (with very good support, but just enough give at the surface not to crush the muscles - a medium layer on the top and 2 firm layers underneath). I would definitely recommend for the following reasons: 1) organic - this was very important to us - and this comes with a proper certificate, they go around the fire retardancy issues by using graphite, which of course is not PERFECT, but it's THE BEST you can do with the current (stupid) law! 2) customize-ability - this was really useful to have. 3) good customer support For us una was a success story! and we would definitely recommend to all our friends. I would not be able to sleep on my OLD, toxic and uncomfortable mattress anymore even if I got paid! will definitely stick to Una for a long while now!