What do you like and dislike about it?
I think the thing I like most is the seat. I thought the plastic brim (at the front) would be annoying at first, but it really isn't that bad. The negative is the backrest - it isn't bad, I just can't decide if it is comfy or not and not sure about the lumbar support. Also, I think a chair would be better with a headrest to lean back into occasionally. I know you can buy third party (Atlas?), but I'm not sure how good they are.
I question whether I should have got the Cosm, maybe even the one with the hammock type arms. That would definitely make a very comfy replacement for a typical living room seat. Resting your head into the long back one is great.
So in general it's a great chair. I love the mesh. I would never go back to synthetic leather or fabric. Especially in summer it's great. We don't usually have AC here in europe.
Also the quality is really high. I bought mine used and the locking mechanism eventually failed. I found a dealer wrote to him my problem and I got replacement parts for 30€. They were easy to install and I also learned how seemingly overbuilt and solid everything is. Every screw you remove is massive.
Sometimes think a headrest would be nice.
I think my main complaint is with the tilt mechanism. I can hardly sit back (even with the chair locked) without actively pushing back. I guess that's suppossed to be level? Anyway I am constantly in one of the forward positions.
Also when unlocking an leaning back - this is hardly usable. If you keep your back straight and your neck straight you are looking at the ceiling. I don't know what that's for. All it does it give me forward head posture since that is the only way I can still look straight ahead so I generally never unlock the chair.
Also the arm rests. They wander. Eventually they will work their way down, no matter how hard I screw them down. So every couple of weeks I notice, loosen them pull them up and tighten down again...
Don't get me wrong it's a great chair. I like the company in general, maybe another model would suit me better. I'm not in market it does a good job. It's just that I think it could be better.