Part of the problem is that a quality drafting chair is expensive. If you're going to set up a standing desk to help your posture, and then cheap out on a chair, it might be somewhat counter productive.
As far as I can tell the adjustable height desk mechanisms are several times more expensive than a decent drafting chair. With a desk that moves I'd also be worried about cords being pulled out and similar issues (my desk especially underneath is a maze of wiring).
