Edit: Anyone have any comment on the Zody?
I have one and I love it. The best thing about it is how easy it is to adjust. Most chairs have a series of knobs and levers that require an instruction manual to figure out and are often difficult enough to operate that people tend to find a good setting and leave it there. The Zody is so easy to adjust I constantly fiddle around with different aspects to change my support needs throughout the day.
For most of the day, the armrests are dropped away down low. As it gets later into the day and I'm really getting tired, they come up and I use them for support. The seatback tension is controlled by a rotating handle which is a revelation if you're used to having to crawl under your chair and adjust the seat back tension with two hands.
It's also especially good if you have torsion in your pelvis that causes you pain. It's the only chair that I know of that has stabilizers around the area of your sacrum to put leveling pressure on both sides of your pelvis to get it straightened out when you sit all the way back in the chair.
The lumbar support system is very gentle, but so gentle that I find it questionable in effectiveness. It's not an issue for me though because I find it so comfortable to sit straight upright in the chair that I don't often ever lean back enough into the lumbar support.
The only drawbacks that I can find is that for some reason the armrests are too easy to move laterally. I've noticed on numerous Zody chairs that it only takes a light push to move the armrests east and west. It's supposed to take more force than that.
It's also a chair that you need to understand in order to get the best use of. People tend to think of their chairs like braces and are disappointed when there's some flex in it or it doesn't hold them up like an exoskeleton or isn't plush like a big sofa. This is the wrong way to think about your chair if you're a healthy person. The Zody has a flexible back that's meant to flex a bit when you lean back into it. It supports your movement, but doesn't stop it. I find that the slight flex makes it less likely for me to slouch when I'm really really tired.
In comparison to most other chairs, there is very little padding, but the seat pan is sculpted in a way that it really seems to feel comfortable with that minimal amount of padding. I tried the gel filled seats and I found that I liked the regular seat padding better. I also prefer regular mesh to leather seats on this chair.
Overall the best thing about it is what I mentioned first. It is such an easy chair to adjust that you'll find yourself unconsciously adjusting it all the time and that is a really smart way to use your chair to keep good posture as your fatigue increases throughout the day.
I've tried chairs that feel better for short periods of time, but I've yet to find a chair that feels as right at hour 15 as it does at hour 1.