My favorite unit is still is still my DC with chaplain attached. Back in the PDF codex I would only have 2-3 on the board, without the chaplain attached at this point, and they'd still wipe the floor with most things. 3 took out a carnifex, 2 zoanthropes, a hive tyrant and then died taking about 6 genestealers with them with the old codices.
I don't use them as much recently(tournament practicing at the moment) but in nearly every casual list I have they're in it.. they're crazier than berzerkers and more powerful it's great
If you shit in one hand and wish in the other we all know which one will fill up faster.
And as I walk in the valley of the shadow of death I will have no fear For I am the scariest mother f*cker in that goddamned valley!
Damn nature, You Scary!!!