Great topic, subscribed (I wished we could).
I had SCE copper gasket - standard type, not ICS -in my SBC 400. I'm a believer that the copper gasket does have benefits in our applications. But does anyone have a magic trick to make them liquid leak-free? (in all fairness, my block deck doess have some cracks common in the 400's). I got tired and put a Fel-Pro PN 1010 in it, so far so good. I had copper o'rings on the block, which I shaved when I ditched the SCE gaskets. I didn't know the ICS didn't require o'rings... it's probably OK for moderate HP, but I can't think how it would seal big HP.
If my decks had smoother finish I'd try a MLS gasket (Fel-Pro or Cometic). Any preference between the two?