I have done two at 150 for 2 hours, and no issues here. Just for info sake, I no longer use Cerakote for anything other than metal. Top grade automotive paints work very well and require no heat. McMillan has been doing it for a very long time with very good results. As for which last longer, IMO, they both do very well. Either will scratch the same, so that's why I no longer see the advantage of going through the whole proccess required for Cerakote on stocks other than color matching to the metal. Another point is that Cerakote cost about $100.00 per quart, and Automotive paint is about $150.00 per gallon which ends up being about 1 1/3 third gallon after adding hardner and reducer. Not kicking Cerakote. I actually promote it every chance I get for metal coating.