I agree. The Embody is a great chair if you have pretty good posture. It is pretty rigid in the center (all the flexibility is on the sides), so that it forces your back into the 'proper' shape like a plastic mold. The problem is, it's a pretty hard chair, so if you have any 'irregularities', like, say, a bit of hunchback (thoracic hyperkyphosis), the hard plastic "pixels" will just dig into your back in all the places that stick out where they shouldn't.
There is a single adjustment knob for the back, but it adjusts the thoracic and the lumbar part at the same time. So if you have a rounded upper back, you'll adjust the knob to make the backrest a more deeply curved S shape to prevent the upper backrest from poking your shoulder blades. But then the lower part of the S gets deeper as well and it starts digging into your lumbar/sacral region. It's not easy to notice -- after 15 minutes in the store, I was in love with the Embody; after 1 hour at home, it felt like my lower back was covered in bruises from the hard plastic.
For this reason, I do not recommend the Embody to people with incorrect posture, or to people who don't like hard chairs.
Other things worth noting are the poor armrests (they have no back movement, so you can't move your chair close to your desk without lowering them) and the fact that you can't really recline very far in this chair because the back tension rises pretty fast after a certain point. Well, you can recline if you adjust the back tension, but it's a continuous knob, so it'll take you ages to go back your regular setting.
I summarize something similar to all this in a deep reply above to the top comment along with some other observations.
I will say that when I was first assigned an Embody at work, I went through a period of comfy->uncomfy->comfy-again, so sometimes sticking it out works. Going through the setup guide (think it came with a DVD even) and putting some work into making it just right helped. Ultimately it became such an important part of my workstation ergos that I dropped a few hundred on one so I could work from home in the same chair as work, and haven't regretted it.
But I totally agree with you--you either fit the profile for it or you don't. I think it's incredibly important that you test the Embody before buying it. If it fits you it's going to be the best chair on the market, hands down, bar none. If it doesn't it's going to be a serious pain.
Regarding reclining, the tilt knob isn't really for active reclining, if I recall their setup guide correctly, more to set the right resistance so you float at an ergonomic 110 degrees while allowing wiggle room to fidget. At the very least, that's how I set mine, and it works pretty well. I feel kind of suspended in the chair that way.
The tilt limiter is set so I don't have much room at all beyond that--that lets me push backwards against the limiter and then arch my (and the chair's) back to stretch.
The arms are crappy. I can't argue there. They sit too far back, and there's too much play in the spread adjuster joint. The height adjustment on them is excellent--they drop well below my elbows so I can use the chair "without" armrests--but the rest of the adjustment is poor.
(To the parent poster, btw, I wear a pretty thick leather belt with mine fine--really does depend on how you're shaped).
I agree that sticking it out can sometimes help. The Embody is very punishing if you slouch (the hard sacral part will just dig into your spine), so the first step would be to make an effort to maintain correct posture. But if you're sitting straight AND still feel discomfort, I'd say the Embody is not for you.
About the reclining, yeah -- Herman Miller would probably say that the chair isn't meant for active reclining, but that's no defense. Sometimes I like to recline at more than 120° to relieve the pressure on my spine (for example, when I'm not typing but for example, watching a YouTube video). I prefer chairs that allow me to do that (e.g. Steelcase Think/Leap/Please, Humanscale Liberty). The fact that the absence of this feature was a design choice by Herman Miller doesn't really change my appraisal of the product.
Funny you should say that the armests sit too far back. I had the opposite problem: they were always bumping on the edge of my desk, so I had to sit further from my desk than I would have liked. And I'm not the only person who had this complaint. I guess everybody is different.
The strange problem that I've experienced, as tszyn mentioned, is that in the shop, after 10/15 minutes, it feels great (to me felt better than the Aeron), then the bad surprise is in the long term.
There is a single adjustment knob for the back, but it adjusts the thoracic and the lumbar part at the same time. So if you have a rounded upper back, you'll adjust the knob to make the backrest a more deeply curved S shape to prevent the upper backrest from poking your shoulder blades. But then the lower part of the S gets deeper as well and it starts digging into your lumbar/sacral region. It's not easy to notice -- after 15 minutes in the store, I was in love with the Embody; after 1 hour at home, it felt like my lower back was covered in bruises from the hard plastic.
For this reason, I do not recommend the Embody to people with incorrect posture, or to people who don't like hard chairs.
Other things worth noting are the poor armrests (they have no back movement, so you can't move your chair close to your desk without lowering them) and the fact that you can't really recline very far in this chair because the back tension rises pretty fast after a certain point. Well, you can recline if you adjust the back tension, but it's a continuous knob, so it'll take you ages to go back your regular setting.