Just watched the DVD, and I have to say I was disappointed by this movie.
On the upside, I thought Jamie Foxx was very good, and showed he can really act, instead of just be a goofball. The last 15 or so minutes is what did it in for me, in that the "suspension of disbelief" factor was
way too high.
And there were two "plot flaws", that just stuck in my craw. Spoiler:
Vincent is a "professional, 'best-of-the-best' hitman", but he doesn't wear gloves or collect his spent shells? (Yeah, yeah yeah, I know. He's so elusive that no one has records of his fingerprints, and he smelts his own guns and bullets so they are untraceable 
) The "ponytail cop" goes into a club that he knows will have quite a few armed people of questionable character, looking for an assassin, and will probably wind up in a firefight, and yet he doesn't put on a vest? Dumbass.