Here is a video of Todd Jarrett shooting an IPSC stage with a hat cam.  It provides a great vantage of how incredibly fast the top shooters are moving while they run these stages.  After the hat cam the video shows him shooting it with a traditional camera view.  Notice his mag transitions.  Very smooth, and always while moving.

[youtube=http://www.youtube.com/watch?v=bAFG5ahTMlQ]