In the final confrontation Ben's son is being held directly to the chest of the villian. In one shot though he is gone to show the damgage, in the next shot he is back where he was before and it becomes appearent that Ben would have had to shoot his son in the head to hit the villian where he did.
During the motorbikes chase, in the mall part. Ben Archer's bike switch from Supermoto to Motocross when he jumps to the first floor from a ramp, then switch back to Supermoto for the rest of the chase.
When the henchmen are leaving the mortuary, one of them is wearing dark glasses, which he takes off as they head down the corridor (presumably in readiness for putting his crash helmet on). But the next time they are seen (exiting the stairwell into an even less well-lit area), he has his glasses on again.
When Ben's son Nick is playing Tekken (when Ben first gets home, and then when Ben starts playing with him), the characters in play on the screen keep changing as Ben and Nick look away from the TV and back: initially Baek and Jin, then Xiaoyu and Xiaoyu, then Baek and Xiaoyu, then Baek and Jin again, then Eddy and Jin.
Toward the final scene of the movie there is an explosion which sets some of the villains on fire. After the explosion, lying on the ground and in full view for several seconds, one of the villains/stuntmen is shown wearing his red fireproof stunt suit.