I can't remember where I first picked it up, but a saying claims, that one should not try to save on things that separate you from the ground. This might include footwear, tires, a bed or chairs. A close friend stopped buying cheap shoes because of that saying. Another one bought a stone pine bed. And here I am today, writing this while sitting on an Aeron office chair at home. Buying an expensive office chair has been a personal on/off topic for several years. I kept wondering again and again if such a chair would be "worth it", or if I might "feel a difference".
A few weeks ago, I stumbled over the website of a supplier which sells Herman Miller products. Their office was in an okay-ish driving distance and so I paid them a visit to try some of their chairs. A nice lady explained every little detail about two products and so, for the first time after thinking about this topic for years, I could sit on an Aeron. At first, I was disappointed. I had built up this moment for so long, that I had expected "something more". But in this moment, a hard truth hit me: It's just a chair. Suddenly, I had doubts. So I dismissed this topic for several weeks, but somehow, it just wouldn't go away. After a long thinking period and after talking with a few friends, I bought that freaking chair. And I love it. The obvious first thing after arriving at home was to replace my previous chair. What I didn't expect was this: after sitting in the new chair for maybe one hour, I stood up and (unconsciously) sat down on my old chair. And it felt horrible. Finally, I got it. My previous mistake was that I did not compare a "normal" chair with something in the price range of an Aeron. Most other chairs just feel inferior, which is a weird situation as I'm not insane enough to buy several of these bad boys. That's a curse I now have to carry.
To finish this off: Obviously, an Aeron is not the best chair in the history of mankind. Other (and more affordable) chairs exist, so get whatever you feel comfortable with. Keep in mind that sitting for long periods of times is unhealthy, even if you have the most amazing chair. So try to get up often, take a walk, grab something to drink or just stare out the window while missing your glorious chair.