I first sat in one when I was on a consulting stint at NASA Houston Texas. Their control rooms are flush with Aeron chairs. They use them because their extended ops require very long sitting sessions and they required a chair that properly supports your body the while allowing 'breathability'..
It took me a little while to get used to my Aeron but once I understood proper ergronomics and learned my preferences (note below) I would't give it up. I have a relatively unrestricted budget as far as a premium office chair goes so my allegience to the Aeron is not lightly made.
Regarding "learning my preferences". That is CRITICAL to ANY good chair. Quite often, a chair that is initially comfortable to sit in doesn't support you well for the long haul. What most people think of as immediately comfortable when 'testing' a chair is often quite removed from what your body
needs for proper posture and ergonomic longevity. If your body isn't supported properly, that initial ooooooh aaaaaaaah comfort feeling will give way to back & neck pain and overall discomfort in the long run.
Initially, I was frustrated with my Aeron. It didn't immediately solve my world problems and just sitting in it didn't change the way I felt at the end of the day. I admit it was quite the disappointment. I then began web surfing to read what others thought about the chair (finally considering that NASA mgiht not have the ball on this one...) and realized that not only are there different sizes of Aeron chairs there are number of key position controls that if configured improperly would render the Aeron as comfortable (or perhaps less) as a $10.00 folding chair. After actually reading the literature, viewing the configuration info on the website and trying different settings for a couple weeks I've finally 'learned my preferences'. There really is a noticeable difference to how you feel in the chair once you know what your body needs and how to configure the chair properly. It's not rocket science by any means; it's technical sense. Not everyone has the same body size/shape and ergonomic needs and there's no set default config on these things. So, out of the box there are going to be a lot of people who get it wrong or just don't get it right without a little learning.
To labor the point; we have quite a few Aeron's in the corporate office. After a few complaints, a call was made to the retailer who sold the units and an ergonmic specialist held a 'clinic' of sorts. Most of the people who'd complained were very pleased with their chairs after the session. Some people still gave theirs up, but there was no shortage of happy recipients.
I'll be buying an Aeron or two for my home office when it's finished. Of course, I'll look around again before I make the purchase just to see if anything better can be bought for the same money; but in the very least I know I'll be pleased with the Aeron.
If you're fortunate enough to find and enjoy an inexpensive chair, more power to ya. But if you're considering an expense in the neighborhood of an Aeron, see if you can test one or at least understand that most of the griping about these things on the internet is from people who don't use them properly. Their likely the same kind of people who gripe that a sleep number bed actually requires
you to figure out what sleep number
you prefer. Then again, some people just can't get comfortable in them no matter how the chair is configured.
I buy through a corporate channel so I get an unusually good price but a quick google search and a little digging nets them for about $600.00 shipped.
Happy sitting