Editing Warhammer 40,000/8th Edition Tactics/Adeptus Custodes (section)

===Sisters of Silence===

Do it. Just do it. You have no reason not to - VERY fluffy, they plug the DTW hole, they make almost no impact on your points tally as a Custodes player, and a Talons force is nearly identical to a pure CustardPimp army in both aesthetically and in play-style. As for how to use them, do you need to be told? Have them hunting psykers, or as bodyguards for Valoris when playing against Aeldari or smite spammers (for obvious reasons). 

Another view is that sisters while incredibly fluffy are not as effective as other options unless you're against armies relying heavily on psychic powers such as Thousand Sons or Eldar. Against an army not relying as heavily on their psykers you have bolter bitches without the faith. Guard make a much better combination with Custodes as they give easy access to both numbers and anti vehicle fire, Marines also give more flexibility and options such as vehicles, psykers than the sisters. As a Custodes player since the changes to smite psychic power is not going to be your biggest problem against most armies. You lose because loads of dice being thrown at your small number of models hurts, tarpitted because sometimes you can't kill quickly enough or because units that deal multiple damage can reliably remove your models such as the Riptide. Guard and Marines will tend to be more flexible and effective options. Unless GW make the Sisters work better alongside Custodes with the Talon of the Emperor changes coming in psychic awakening it's arguably better to go with Guard or Marines.

With the release of War of the Spider, Sisters of Silence can now be taken in a detachment of Adeptus Custodes without the Custodes losing any benefits such as Sworn Guardians or The Emperor’s Chosen. The Sisters do not gain those abilities.