intake manifold end seals

Sure I remove the dowl pins and use a bead of silicone like most everyone else today.
Either will work for a time and either will fail with cause.
The cause that would push either out from under the intake was a clogged PCV system or simply more blow by the a resticted PCV system could carry. The weakest link in the crankcase sealing is where the cork can rotate and/or break at those little round dowl pins. Just the indication of another problem that needs to addressed.
I know a guy who put valve cover gaskets on a chevy engine 3 times before he figured out the clogged PCV system was why the gasket would roll off and out at the rear of the right cover almost imediately.