I just don't think people realize what they're screwing with here. Let's throw out the Borg collective or Minority Report possibilities for the moment. I'm not an Einsteinian genius, my abilities are more about patterns, organization, logistics and perception. Things going from A to B and all the possibilities and permutations of how it may play out. Game theory. Strategy. How to make things more efficient, quicker, short cuts.
Now imagine that kind of mind, but opportunistic and full of criminal intent. Then give them Limitless the movie type abilities with one of these chips. Say in the financial world, you'd create a Michael Milliken on steriods. He'd be able to create a complete empire of fraud and cheating and hide it, raking in billions if not trillions over time.
Or someone that could walk into a room, assess it in an instant, and with on-the-fly tactics and strategy kill everyone in it with little more than reflexes, technique, and minimal weapons, simply by being enhanced mentally by a chip.
It would be a boon to criminals and megalomaniacs. And the list goes on.