Back in 2017 I had my Hemi GTX convertible done in ceramic at a detail shop. First I had a guy touch up a few paint chips, then the detail shop clay barred the car and applied a ceramic coating. The whole process really woke up the paint. I have no way of knowing whether the clay bar, or the ceramic coating, or a combination was key in bringing out the results. But I think it looks pretty good for 50-year-old paint. As far as longevity, It still looks just as good 5 years later. But that doesn't necessarily mean much, because the car is kept indoors under a cover when I'm not driving it so it doesn't get much long-term exposure to the elements.