I can speak to this topic as an end-user and car guy, but not as a technical expert.
The first thing to know is that these coatings are not intended as a replacement for film, but rather for wax. They aren't going to protect from chips. They have superb UV protection. When expertly placed on a flawlessly prepped surface, they can maintain the gloss and depth of the best fresh wax you have ever seen, for years with no maintenance other than washing. If a car has a new film in excellent condition, the coating can be placed on top of the film to also improve it's appearance and performance.
A year ago, I had some paint work done on my Supra by an exclusive high-end one-man shop here in Denver. Although he doesn't do any ceramic coatings himself, he said the technology had matured to be the real-deal. He strongly recommended I look into the C-quartz product line. An often-mentioned competitor is Opticoat.
http://www.cquartz.com
Their highest-end coating, CQuartz finest, is available only through shops that have been manufacturer-trained.
http://www.cqfinest.com
There is only one such certified shop in the state of CO, so that is where I ended up taking the car and getting the top-of-the line coating.
The result factored into my second-in-class finish at CO's most prestigious car show
I am scheduled to take the GT to the same shop tomorrow. However, the owner just informed me that CarPro/CQuartz is just about to release a new top of the line product that is supposed to be (of course) a major step forward in the technology. He is calling to see if he can get a pre-release sample over-nighted, if not I'll be rescheduling to get this latest/greatest coating on the Tungsten.