I recently (about a month ago) painted my calipers red to contrast the silver wheels and black body. I used regular 'ol enamel, not hi temp. I had read many many too many posts about the benefits of using capliper paint kits, hi-temp paint, etc. etc. I think I spent about $3.50 for a spray can full of Ford Red paint. I spent another couple of bucks on some brake cleaner. Another couple on a fine artists brush.
The calipers turned out wonderfully. From what I read, hi-temp paint must be exposed to high temps for it to properly cure, and most calipers do not see that kind of heat. Since I used a spray paint, it set up pretty quickly. I jacked one side of the car, took off both wheels, and alternated activities between the two. By the time I got to the other wheel, it had dried sufficiently to recoat. I removed one caliper, but did NOT need to. Using the artist brush and spray paint, I was able to paint the calipers very nicely with a little care. In fact, it was easier than having to try to maneuver it with one hand and paint with another.
Long story short.... I do not think hi-temp paint is necessary OR recommended. JMHO.
Jeff