I have used VHT Header Paint on the headers. So far so good, but I haven't gone more than about 2 miles on my bike yet, so maybe not a reliable recommendation yet. I am not sure if they offer anything other than flat black for this particular paint.
I used Duplicolor high-temp engine enamel for my engine. While others seem to have had great success with this, I've found that it chips pretty easily. However, this could have to do with my prep. For example, I used a soda blaster on the engine, and I've since learned of adhesion issues that can occur if you paint after soda blasting.
One recommendation would be to paint the engine in aluminum color. I am now realizing why so many people (and the factory) did this. Chips/scratches/etc are far less noticeable. I painted in a dark gray/green and they're very noticeable.
Btw, I believe Duplicolor owns VHT.
You could also look at POR's offerings. Some of their paints have excellent self-leveling characteristics so you can even brush them on, and they're thick and tough.
Aaron