Valve Cover Gaskets

What's wrong with cork gaskets? I've used them for years for no problem. Just glue them to the valve cover and don't over tighten them. I never had them leak and have been able the take the valve covers off and reinstall with no leaks.
What he said. I had Bazza's 318 valve covers off about 3-4 times. and still- no leaks when we took the car back.

(FelPro's, by the way.)