Usually they’re bad against Chaos Spawns.
Today I saw them lose a fight to a Chaos Spawn in an open area, stacked on top of each other tanking hits. There was no other enemies present. Just the Chaos Spawn (it was a Boss chest on Chaos Wastes). They was blocking and dodging at weird times and all just got hit, with no terrain blocking them either.
I don’t know if Chaos Spawns attack speed got increased or something, but they should definitely not lose to just the Spawn alone, as without stuns, and with bad luck on aggro, there’s no possible way to stop the Spawn free killing all 3 bots.