One of the challenges I've had recently when playing DE is anti-vehicle. Dark light and haywire scourge are good but seem to be hit and miss with the results it produces. With the updates to DA and SMs, my local area has a lot more vehicles than usual and looking for something that could be a bit more decent from a survivability and general effectiveness.
Looking at other options, I'm considering taking a Cult Mechanicus CAD or Formation of 1 Tech Priest and 2 units of Breachers. The CAD would give me additional Troops that can take Haywire or Grav while the Formation allows the units to Deep Strike (so lose ObjSec - gain Deep strike). They are desperate allies so I would have to deal with One-Eye-Open but otherwise I'm thinking they may be better than relying so much on pure DE alternatives. This would also allow me to supplement using DE and/or focus on anti-infantry.
Has anyone ran this combo or even ran Cult Mechanicus? I'm curious to get everyone's thoughts on this idea as the alternative I'm considering is to take a Haywire Corpsethief formation for a lot more points.