In 60+ years of doing professional mechanic work, I've never been able to find a sealer that will stand up to exhaust gas temperature. Now, in about 3-2-1 seconds, somebody who has read three copies of Hot Rod Magazine and found at least five internet references will tell you I don't know what I'm talking about. It's up to you to choose who to believe. The only cure for pitted gasket surfaces is a milling machine and a fly cutter.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!