Long term Markus user.

I am unfortunately not tall enough to fit the ergonomic of this chair.
So in order for a proper height , I need a little leg rest so my leg is not hanging ( recommended to get some leg rest if you need some height to match the table, even stool work)
The Mesh back and recline angle work well. It hold up for me over 10 year+ maybe.
The seat cushion give way after awhile 5 year or so ? You could repair it DIY by buying foam and reassemble them , but I am lazy to do it.
The Base, pump and spring is actually pretty good, heavy and still not giving way , except for the spinning wheel in the hydraulic pump (grindy sound).
The wheel after 9 year or so, start to pick up dirt. My hard flood is fine with the wheel, if you need replacement however , ikea caster dimension is a little different from others, but you could still upgrade it (just go shopee).
The leather is peeling here and there abit , just a little speckle not as terrible as some gaming chair , imagine like acne spot, haha .
It does get warm a little on the leg sometime , but I change my position usually , fold my leg , put both my leg up , sit at a side etc. Combination of aircon and room temp uses, just give it a wipe for normal maintenance.
The Armrest feel ok, but get in the way if you try to sit closer for better arm position and its not adjustable. However the armrest wasn't always use when my hair is on table.