It was a 8.5 for me after the main story, but then it became a buggy mess.
I fell through the streets every 30 minutes. Wei didn't move after accessing the TV for the drug busts. Missing animations where the game didn't let me enter a car. Music that was suddenly gone. Accessing the map or the menu took a minute sometimes. The game froze on me twice.
There was more that I probably don't remember anymore.
It's hilarious though. During the main mission I had almost none of these issues. After doing all side missions/events/jobs and getting all collectibles it transformed into an nearly unplayable game.
7.0 would be my final score now.
360 version btw. with the newest update.