Thermal coatings and providers

I have several local powder coating companies that advertise ceramic coatings. My question revolves around types and processes.
I have always thought the coating was a proprietary process that is better left to the big companies like Jet-Hot Coatings. There traditionally hasn’t been many companies that did ceramic but now it seems like every powder coater does ceramic.
Did ceramic become more available? Did a patent expire? Did materials or application/curing equipment become more available?
Final question: Can you trust Joe Blow Powder Coating ceramic coating to be as durable and effective as the more well known traditional ceramic coasters like Jet-Hot?
I’ve got some stainless eBay headers for my 5.9 Jeep I would like done. ZJ Grand Cherokees are notorious for under hood heat and I would like to see if ceramic coating is the real deal.

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PS, this is not the 5.9. Just test fitting. The Jeep's 5.9 has a truck pan and I was looking at the clearances to the sides of the pan rails.