One caveat - I have been investigating the same: Most of the various coatings require a "correct" cure for proper performance. Jet-Hot, VHT paint, etc. The paint needs to be applied to a properly prepared surface, then baked to a certain recipe within a certain time frame.
Jet-hot and a local high temp powder coat outfit do not advise using their respective products on a newly rebuilt engine. They each have a specific engine running sequence after installation. The coatings may fail during the break-in procedure for a rebuilt engine.
Another option is to use Calyx Manifold Dressing. Easy to apply and looks great. But the coating does not "cure", and will rub off if you touch it. Working on the engine, for example. Fortunately this is not a concern on our LBCs, as the reliability puts Toyota to shame.