I would have to respectfully disagree. A scope is the last thing you want. Too hard to use in low light situations or on close in, fast moving targets due to the narrow field of view. Good old iron sights would be best for such a situation. In most urban settings, you just wouldn't have much need for a very long range shot, requiring a scope anyway.
Fine...I assume that is why our fine young men trained as snipers never use a scope and rely on iron......doh!
Iron sights are fine for close-range....as far as light acquisition, spend the dollars required for a low-light or night scope...
If I am facing a hostile opponent and he has a scope....I guess my iron sights will even the playing field...
/sarcasm