I DO NOT usually promote products, but I have purchased a chair such as the one you showed a picture of, however I did not purchase that exact one. My chiropractor has a couple of that model and I was able to try it out in his office. I discovered quickly that it was just too tall for my short legs. So I went out and purchased this model instead: FitBall Exercise Ball Chair with Ball (about $80)




What's really cool about it is that the legs are height adjustable, as is the lumbar support, so you don't have to worry about it being too tall or too short. It took a couple days to fill the ball up completely, but it was worth it. It also doubles as a holder for your exercise ball, so you can just pop it off and do some exercises, which is a nice space saver. I don't use it as much as I should, mainly because I have an S1 nerve problem, but it definitely gives me better posture than sitting in my regular computer chair.

Another chair I've purchased was by Kline Design http://www.kleindesign.com/. They actually make their ergonomic lounge chairs and couches to your preference, though they are a bit spendy and only come in a few styles. I also just use a lumbar support when sitting in chairs that are too cushy, though usually I just try to avoid those (have not sat on my couch for over a year). Anything that makes my spine curve forwards, which pushes my shoulders and head down, is awful.

Take care,
Melissa