On my duty gun I use Loctite 243- It's the medium strength but oil resistant one. Regular blue (242) and others are not oil resistant-

Another vote for VC-3 and I would also add a strong vote for aftermarket mounting plates. I use and like the C&H Precision plates as they fill in the gaps on the MOS slide and keep lateral pressure off the mounting screws under recoil. There are stories on the internet of screws being sheared off under recoil but I’ve never known anyone who has actually witnessed such an event. A good trick once the screws have been tightened to the required torque specs is to mark the screw and RMR with a marker to quickly check that the screws are not blacking out.