I found that it worked quite well. The two big things are look for a slower speed section of the track and it helps if the body is a solid primary color (or mostly so) that contrasts well with the track surface. Make sure that the camera can see the entire section of the track.

The latest revision of the software lets you tweak camera settings, and this helps get things sorted out. If your camera angle or placement ends up seeing too much of the track, you can also size/shape the sensor area, too.

All in all, it's perfect for small club racing or practice night where you don't have access to the primary timing computer. The only extra gear for me is a tripod and the camera itself.