RTV, Permatex, Aviation Form-A-Gasket, The right stuff etc....

The right stuff is the wrong stuff to use on an engine. unless you are not using a gasket. It is strictly a gasket maker.
You may as well use JB weld epoxy. imo
Don't compare it to ultra, because with ultra you don't need a chisel to get it off.

Well, having never used it and planning to never use it, I don't know the difference. Thanks.