I basically sit in my office chair 7 hours of my 8 hour work day. I need something that is comfortable, adjustable and durable.
I have found this in the Knoll RPM swivel tilt chair w/ergonomic controls which we were told was perfect for someone needing this most of the day, every day of the work week. If I'm not comfortable, I'm not working at my best ability.
This chair has it all:
High back support with a 4" height adjustment. Once I adjusted it to the height I liked I have not had to change the position at all.
5-position tilt lock. Once again I f ound the most comfortable position for me when sitting at my keyboard all day and this really reduced the strain on my back. The control knobs are easily accessible if I want to change the position.
It has a 360 degree swivel. This is great when I am moving back and forth to the file cabinet on the side of my desk or to the cabinets behind me. The castors glide smoothly with little effort.
Soft, ergonomically shaped armpads. These are also adjustable up or down or in and out to the sides which is a great feature and one I use the most.
The material is a knit pattern and stretchy to move with me as I get in and out of my chair. It still looks as nice and new as when it was purchased almost 3 years ago. I chose the basic one color grey option, my boss chose the black on grey pattern and there were many more to choose from.
The price of this chair might seem a little expensive but when you need to be comfortable in one chair all day this would be the one I would recommend.
Update On Mar 14, 2010: This office chair shows no signs of wearing down at all. The material looks as good as the day I got it and the cushions are still "cushy", very important when you sitting at your computer the majority of the day. Spending a little more money was definitely worth it!