I am still undecided about coatings, here is why.

We know running aluminum heads can allow you around another full point of compression vs an otherwise identical iron head, the reason is it conducts the heat away from any hot spot faster so the hottest point in the chamber is no longer as hot and no longer as likely to pre-ignite the fuel. Same with the piston, the heat can spread out faster from any given point. Now we would add a ceramic coating that does the exact opposite...? It is possible I am missing something, maybe just keeping the heat from being absorbed in the first place outweighs it but my though is that it would just have a hot spot with the piston behind it still trying to transfer heat evenly through out but the surface could more easily develop a hot spot, sort of an in between of the properties of aluminum and iron...

One other thing I like to do that seems to work really well for me is running as flat a piston as possible, for example a 318 with stock flat top pistons, no valve reliefs set with a real tight quench and magnum heads let me get away with very high compression, lowest surface area possible for a piston to keep it from absorbing heat... it may be worthwhile to run a head with a bigger chamber so you can run less or no dish in the piston. I always prefer a perfectly flat piston if possible.