Herald Caller and Fiendish Vessel

[Galatina91]

Are those two Cleric archetypes, Herald Caller and Fiendish Vessel, compatible?
I am unsure about this because they both restrict the list of possible summoned monsters and both have influence on the domains the Cleric can pick, but they do not explicitly modify those abilities (I mean, it's not stated "this ability alters/replaces..." etc in both the archetypes, only in one of them), and it's actually possible to have a Tiefling Cleric with only the Evil domain and the Devil subdomain, with a _very_ restricted summoning list...

Another unrelated question, about Sacred Summons and all those abilities that give the possibility to summon a monster with a standard action instead that a full-round action: If you summon a monster with a standard action, can the monster act in your round, or does it simply stay there, able to flank and make attack of opportunity if needed, until your next turn?

[Blake's Tiger]

In PFS they are probably not compatible due to the recent FAQ.

However, I would allow it in a home game. FV doesn't reduce your domains (like Asmodean Advocate) only restricts what you can select.

I believe attacking on the turn they're summoned is a function of the SM spell, and Sacred Summons does not overrule that, so they may act.