The Pacifier feels weird. Tried it against Predator bugs, it feels good to shoot, and it completely stunlocks medium enemies like hive guards or commanders. But after dumping a full mag into one, it's still alive and we're both left standing there awkwardly staring at each other. The stun lasts just short of reloading another mag, so you can still clear them, but it takes way too much ammo and time, and risks you getting swarmed while it's going on.
At least it's a legitimately good crowd control weapon. You can spray across 3 commanders and back off safely, but you still have the problem of killing them at the end. I had a few good moments saving teammates who were getting swarmed, giving them enough time to escape; but I was then relying on them or on sentries to finish the job.
Maybe it's worth bringing for Illuminate, to get breathing room on the lower HP Voteless swarms and space from Overseers. But I finally burned out on fighting them, so I'll test it later.