[Mitch Ives]"Anybody using Color fast from New Blue FX?"
I am. I've only done a little work with it so far so I'm still learning it. The controls take a bit of getting used to. It seems great for quick fixes and you can quickly get some nice looks. The shape mask is pretty cool. For more complex grades, I would probably go with something that has color wheels. I think you can download a free trial if you want to check it out.
I'm playing with it as well. Biggest upside is the ability to select the range rather than live with Color Board's choice of where shadows, mids, highs, begin/end/taper. The biggest down (IMHO) is the UI. I don't like coloring with sliders. There are Noise Industry plugins that address that in interesting ways, such as Moods and Levels and Curves.