Now I'm also on a 9cm thick Visco Topper, H2-3, RG 80, and so it goes, because I now better lie with my body to the cushion.
Since I like to sleep alternately on the page, often with arm underneath it and from left to right, the pad is a little too long and too wide. Too broad, because my bed now with 2m bed length and 40cm cushion width is slightly too short, when I stretch myself. Bin 184cm tall and quite heavy. Pleasant is that it is not so very hard when I put my arm.
But it is a much better cushion for me as a feather or polyester pillows, so I'm happy, until I find something better.