Antitank: War Walkers, Ravagers, or other?

so Im thinking of putting some war walkers or Ravagers into a Ynnari list for some lance destruction power. Which one is better/more point efficient...or is it better to run something completely different?

I havent built a list yet, but the general idea is to have two units of Shadow Spectres, A unit of Dark Reapers, three units of Rangers. Yvraine, Farseer on a bike...and whatever else I can fit

Little less resilient, but you can use scourges (as they'll proc soulburst).

I've read here that a player used to use 2 squads of 5 (3 or 4 dark lances each) far away as sniper team/objective control.

If your opponent kills one, you got a massive heavy counter fire as the other squad will soulburst (psychological warfare *-*).
If Yvraine sits back, she can also make one of the squad fire twice thanks to the psychic power, bringing them to 12 dark lances shots per turn..

And it's not mandatory to set them in reserves if you want to avoid the 4+ to hit on the first turn (hide them behind a vehicule).

But if you do drop a squad in, or move then the 4 dark lances will still fire with the equivalent ability of a ravager. A vary favourable comparison for a squad that can deepstrike in unhurt and then fire off two ravagers worth of firepower (w soulburst)

They also proc every time any unit near them dies. 3shooting phases a battle round, if the enemy doesn't use long range firepower on them. Love the psychological angle