The voice acting was meh overall.
David Hayter was something quite special. Still get nostalgia when I hear his voice in the older games.
You know, I used to be angry because of the removal of David Hayter, but in the end I finally understand the people who say that he "would not fit the tone of this game".
They were right all along. Hayter could never fit in a game with such a bland, boring and uninspired story where all the characters have paper-thin depth and zero charisma. Hayter would've provided some charm, and God forbids we could have something like that in MGSV.
Now I'm actually glad he was not in the game. The man did not deserve to play the worst version of a Snake to date.