This is not a comfortable chair. Lumbar support is great but seat puts too much pressure on legs (and not backside). I need to get up frequently due to pain in my hamstrings.
It's good but the wheels were kind of sticking so I replaced them with the wheels from the original chair. Also the headrest doesn't tilt back and forth as easily or slide up and down but that's actually a really good thing because on the old one it too easily slipped down when I didn't want it to. I'm guessing this level of stiffness is actually correct and it was the old chair that had it wrong.