I haven't seen it mentioned here so wondered if anyone had ever tried the so called special paints advertised for brake calipers and whether they are any good. The original finish ex works seems just like dark bare metal and cleaning/polishing does nothing to change it.

I've used caliper paint with good results on older sport car calipers that probably get hotter than bike calipers

Car calipers are probably a lot less vulnerable to flying debris. I think it will chip but you can always touch up. The heat issue is nothing to worry about. My engine paint has held up fine except it has gotten a bit darker and less intense in hue. It also gets gravel embedded in it. Apparently it softens up when hot. I doubt very much that will happen to your calipers, being out in the open and not getting nearly as hot. I would not apply anything that has any gloss to it. Flat only.

Cruderudy/Rook... thanks for the words I am gonna give it a go, it cant look much worse than the current finish if I do it carefully.

Brake fluid will take fresh paint right off, I'm sure. ...but if you're careful when you bleed them, you should be ok. Touch ups.