a thousand emotionless killing machines > company of marines
Maybe if his PMC is budget-less but it'd be cheaper to rent some marines than to research, develop, and produce a horde of terminators.
It'd just be cheaper to replace and maintain your human force in the long run than to spend a king's ransom upkeeping a bunch of robots, because of your humans can have their own salary and do whatever to keep themselves maintained instead of robots who require bottle feeding after every scrap they get into. Have you ever had someone throw a rock at your 900,000 USD Ferrari? You will know the pain of it when your robot gets loving hit in his LED eyeballs and you need to have his entire head replaced.
On the topic of giving rights to Sentient/Sapient robots/AI, I'm not going to be in any goddamn mood if my loveboot9000 suddenly doesn't want to blow me because it has a headache. Giving them rights would be a mistake because that would grant them higher authority outside of what they are: inanimate tools to accomplish stuff.