It worked well. I have an extension arm (mounted to the wall), a slim humancentric CPU bracket, then the keyboard tray, and finally a monitor. My extension arm holds a large 36" monitor, and so the extension arm is heavy duty and is rated for a large TV to hold the weight of the CPU, Tray, and larger monitor.
I particularly liked the tray, as it pivots vertically, so I can have the tray at a slight downward tilt.
The set screw that holds the mount onto the wall bracket is almost impossible to reach, I needed two extenders for my screw driver to be able to reach it. You need to completely un mount the stand to adjust the monitor