The coatings are easily removed from areas that may need repair/welding - this leaves the rest of the system protected at the very least. I have seen some ceramic coatings that appear to be almost see-thru for that natural metal look. If you have a polished SS header and want to maintain that look, you can have just the insides (virgin-clean metal only) ceramic coated. Works wonders in keeping underhood temps in check Without having to wrap or jacket the exhaust.