Just finished watching it. Excellent way to end it. Genius. You instinctively want everything tied up nice and neat, because that is what most TV will give you. They resolved the characters without feeling the need to have a "happy" ending, and in doing so made a real comment about how real life actually works.
I have to admit to feeling a bit cheated on Omar though. While I would concede that the manner of his death fits in with the way they ended the series, I wanted more for him. I really wanted him to get Marlo.