Boy I'd also like some re-assurance on which lower gaskets are best. I have a picture here of three gaskets. The one on the left (red silicone beads) is the Fel-Pro (which I used). The one in the middle is the new GM, and the one on the right is the one I took out of my 1999 which had dumped all of the coolant into the oil.
(the picture is pretty large, you'll have to scroll around to see it all)
-click on the above link for the picture-
The main reason I used the Fel-Pro (-other than their good reputation on all of the Chevy V-8 applications I have used through the years) is that you will notice that the Fel-Pro set does not have those mysterious notches in the coolant ports. AND, you might notice on my failed set of stock GM gaskets, the worst failure was right there at those stupid notches.
:( "GEEEEZZ, I DON'T KNOW which are best. :( Actually, I not too sure that any of them are any good. Just think of the thousands and thousands of small block chevys out there running aftermarket aluminum manifolds, on iron heads and iron blocks, using the good old standard flat non-high-tech gaskests, AND NEVER FAILING
(somehow, I think this fancy plastic/silicone gasket idea was just another one of GM'* bad ideas, -almost as bad as putting the hot EGR pipe up through the plastic plenum)
My gosh GM !! What are you doing to your "faithful followers?"