Check your Topix again you should see something like this, which is a screen dump of my Topix for MY17 HSE Lux
This shows 8 weight seat adjustment plus 2 way lumbar, now when I went to school 8 + 2 = 10.
All this is a bit of a marketing con, the seat goes up and down and this is counted as 2 adjustments, backwards and forwards and all other adjustments similarly, so in reality you only get a 5 way adjustment if you have lumbar support, and 4 way if you don't.
My electrically adjustable lumbar support works OK, very obvious when you adjust it.