I have mine coated, did it myself using a Eastwood home unit and old oven. My dads engine has everything powered except the block and heads (Pontiac V8) and has held up well for a many years. Engines only get to 200 degrees or so, powder cures at 400, so it holds up just fine. Dark colors hold better then light. I had mine Chrome Silver which looked good, but seeping gas discolored it. I went with black this time and have had no problems.
Joe