best sealing valve cover gasket on the market?

Hi, swapping the black MP covers for a set of polished aluminum on my built lil 440 and I want to use a good sealing gasket now while its on the stand instead of it leaking down the road in the tight little fish. I have a set of Mr. Gasket 5877 hanging on the wall but I wasn't sure about them as they are basically cork. Now I am new to performance based engines but in the late 80 to very early 90's my dad had a '79 W200 with a tired 318 and I remember swapping one set of leaking cork gaskets after another (valve covers/tranny pan). When we swapped to a rubber the leaks stopped. So since I spend 95% of my time working on Cummins' trucks and they believe in nothing but rubber I thought I would reach out to some of my Mopar brethren and learn from your tried and true mistakes. So let me know? What cover gaskets (brand and part #) do you use and swear by to keep oil in the engine? Thank you:)

Specs, cast iron heads and brand new polished cast aluminum covers.