Bo,
I've run with a ceramic coated piston for 3 years without any indication of overheating, although I did go with a new piston this year because the clearance was up to .007" Bottom of the piston is a caramel color and the top is just the color of the ceramic with an even gray coating. Head has even coloring with the valves (titanium) a lighter yellow tinge. This year I had 14 to 1 CR with a 92mm piston, 250 psi cranking pressure, twin plugs, and ran 110K without a glitch. And then a very knowledgeable friend told me I should be using a different gas that would burn faster and make more power! I dunno, but the old thing just keeps running and getting faster!
I don't think you will have any problems with 12.5 to 1 and 110K, and I like the ceramic coating for the extra protection for the piston.
Tom