We have these at my office. I love them. Health benefits aside, these are ideal for code reviews. People don't have to crouch or drag chairs into an (already too small) cube.
Other benefits include: nobody sneaks up on you, while you're standing, and it helps wake me up after lunch.
That being said though, most people use them in sit down mode and forget to raise them, most of the time. Still, it's wonderful to have the option.