I know the op has already bought a chair but a relatively inexpensive alternative is the Autonomous ergo chair 2. I bought one to replace an IKEA Markus and it’s night and day better. I’d recommend for someone in the market that doesn’t want to spend HM money but wants something similar.
No there not as well built as a HM but for £300ish I haven’t seen anything better for a brand new chair.
The Markus is just overrated IMO. The seat padding just didn’t hold up and compressed to nothing very quickly, it lacked lower back support and wasn’t adjustable. Mine was only a couple of years old.
I ended up getting one of the autonomous sit stand desks too which is decent for the money.