I am very happy with my Supreme ergonomic chair. It is very comfortable and adjustable in so many ways. The arms are adjustable for multiple positions albeit I feel they are naturally a little too wide. for my frame. It's a solid, well-built chair with quality parts . It assembled fairly easily with good instructions. Overall, very happy with the purchase. You get what you pay for with office chairs and this is a worthy investment.

The Ergotune is a nice quality chair, but I do have a few gripes:
* The packaging is extremely unsustainable, with masses of foam inserts, plastic bags and bubble wrap. Expect to fill up your bins with packaging if you chuck it all out at once.
* The arms are not particularly adjustable - it would be nice if they could be brought closer in to one's body
* There could be better padding at the edges of the mesh parts, which, with the exception of the waterfall front of the seat pan, are just mesh over hard plastic.
* The arm rests could be softer
* The arm and head adjustments could do with a locking mechanism, as I find myself bumping them unintentionally a lot
* The adjustment levers (height, inclination resistance, seat pan depth, seat pan lock) could be better placed, as I find myself having to lean over to access them, which is difficult when adjusting the chair
All of these may just be "me" issues, as I am fairly short though.
Also I have read some reveiews complaining about the longevity of the chair, which remains to be seen (I've had it for 2 weeks).

Very nice chair my whole family was a bit mad until they sat in it at one point I even saw my dad sleeping in it

Better than expected, solid chair all around

Great chair.. only gripe is I wish you could lock headrest.. but that’s mainly due to the wife leaning on it thinking it won’t move (never moves/slips due to ‘normal’ usage).
But great support and customization option :)