Can second the steelcase leap. Get one cheap off of craigslist and re-upholster it if thats a problem. If you're swimmin in cash and can buy new, thats cool too. This chair is incredible for long sessions.

I've had the Ikea malkolm for about 2 years, but had to pay around $150 aus, so around $125 US. For that price, the plastic material is pretty average quality. This is especially noticeable on the armrests, where there are lots of loose or ripped off areas. The connection between the base and the seating also feels dodgy/loose, and has been since I bought it. It feels as though it's got a couple degrees of movement in each direction (when in the locked position), despite everything being screwed in tightly. You may be able to get a feel for this if you try it in store.

I won't be buying the same chair again, but the inflated Aus price compared to others I've seen quoted in this thread is a big factor.