Just to show how good the strongest AI players are, here are three games records.
The first one is between Zen and CrazyStone in the final game of the UEC Cup computer Go tournament.
As can be seen the AI players can still make quite simple mistakes - for example after move 228 Zen failed to see that playing B11 can win that capturing race.
The second is a 4-stone handicap game between Zen and Ishida Yoshio 9-dan.
The third is a 4-stone handicap game between CrazyStone and Ishida Yoshio 9-dan.