To be honest, he’s too slow. In a firefight, you can expect to absorb every single one of your enemies bullets.
In a situation where you can succesfully surprise your enemy (Execution mode) then he is very effective. In something like Objective/Stopwatch, he is much better suited for defense. He won’t need to move as much, and can choose when to disengage. While attacking, he would just be too disadvantaged.