I agree. I don't think this paint would be a problem on grills if it was used in the same manner as regular grill paint.
I have not seen this in stores before, but it boasts a 2000 degree heat tolerance which is 800 degrees higher than regular rustoleum high heat. The "Ceramic" claim makes it sound durable, which would be great, but like Larry says, I really don't think it is really ceramic. That stuff needs to be baked on at temps much higher than even 2000 degrees.
Would it work well on grills and grill parts? Maybe. I would certainly like to know. If it comes available near me, I will probably grab a can to check it out. Price could also be a factor. How much did a can of that stuff cost?
Oh, I just notice that it is a FLAT black. That would maybe make it usable on the cook box IMO. The CERAMIC claim had me thinking it was a more glossy finish.