Zeta Imperial Probe Droid Or Nihilus unique zeta?

The problem is that if you are facing a RJT team with zzR2, then the opponents will cleanse the Target Lock every time they crit. Which means that they cleanse it pretty much immediately.
So, in reality, without something like Plague also on the opponents, so that debuffs can't be cleansed, Target Lock is pointless.
(I have Probot zeta'd, so this is based on experience)