All I can say is after having to re-paint the exhaust ports a dozen times or more with Bill Hirsch paint, I have finally got one that is not burning off. However the color is not as pretty as Bill Hirschs.
I like the color that Bill Hirsch's has which is why I don't think I would do the whole motor. I Think I would continue to use Bill's on the motor and just use the KBS on the very hot spots.
It will not match exact but it looks better then burned off paint. If you want to match exact, then do the whole motor in KBS paints.
Here is a picture were someone did the whole motor. It is out in natural light. The Pontiac Blue Metallic is not as nice as Bill Hirsch. Don't know what color they painted the intake.