I found this unit to be extremely heavy and bulky, unstable, and unergonomic. It made some kind of dirty metal shavings, like a graphite powder, every time I would change height, leaving stains on my desktop and hands. Wouldn't reach high enough for my husband, and he's tall but not terribly tall. The keyboard tray droops a few degrees and places your mouse way too far back, it hurt too much to use. Makes clanging noises and you have to press down REALLY hard to get it to the bottom position. I ended up returning it and buying a ZipLift, which have LOVED every since.