Yes. I guess it's more of Asimov's law, or maybe the Astroboy theme is too instilled within my mind. I know droids can kill people - I watched entire Clone Wars. But at least all the prequels had the droids = enemy (or, more like... hmm.. Zombies)... But in my memory, none of the good side droids intentionally killed a human being. (Well, they aided, but not on their own).
One scene though, is R2 killing off other droids in revenge of sith, or R2 fighting the death battle against R4... but at least it's droid vs droids, not droid vs living thing.
So my understanding of droids on human side = comic reliefs and aids, but not a war mongering machines - but disney's droids like chopper & K2, seem to be much more self-conscious than other human side droids, including 3po.
To think finding Obi-Wan as pure retcon, the dialogues in Rogue One between Organa and Man Mothma seem to direct too much linkage & intent finding Obi-Wan... so I guess I will just have to assume Leia, being pursued, had chose to fled to Tatooine in desperate attempt to ditch the droids to Obi Wan, instead of giving to any other rebel person... which seems to make most sense. But coming to that much trust without ever meeting Obi-Wan himself with such valued information, seem a bit unlikely or dare I say.. far-fetched a bit.