I just use black silicone sealer myself.
I only use it VERY lightly, and only around the water ports.
It is one of the few places I put a light smear of RTV on both sides of the gasket.
Usually I just put a super thin layer on one side of the gasket, the side that is easier to clean, IF I use it at all. But in the case of the water ports on the heads, there is usually pits and corrosion wear on both parts, so a thin coat is best IMO.
Then I put a dab in the 4 corners, enough to squish a bit.
If you can help it, use the gasket set with rubber ends, instead of cork.
If I use cork, I will put the RTV under the cork, against the block, and allow the RTV to dry quite a bit before installing the intake.
(You must clean the block end surface well if you are going to do this, RTV won't stick well to metal that has oil residue on it.)
I never use just silicone at the ends. That always turn into a huge mess, even if it does seal. I never have issues with rubber or cork if it's done right. Do it lazy, it won't work.