I rate the use of location as their strength because it has a really urban and grimy atmosphere and builds a lot of tension and mood. I especially like the use of close ups - like the barbed wire shot.
If I'm being honest, I think their opening is absolutely amazing - there's not much i can fault. If I had to point out one thing it would be, to make their match on action shots a little neater, so it flows much more smoother.
They don't need to change anything, except the match on action shots flowing smoother.
The still need to make the overall project look more professional, because they have all of the titles, soundtrack/backing track and a variety of shots.