Has anyone had any experience, good or bad, with DYI ceramic coating? I have sever adds for various products touted as ceramic coating. Most look to be a simple spray on and wipe off type product. Anyone have experience with these? Are they any good? While I don't doubt that they are inferior to a detailer applied professional ceramic coat, that's not really my question. Looking to see if any of these products are worth doing. If so, which ones work well?