What is the final impression of Rip Van Winkle?

Assuming you mean what final opinion readers are left with about Rip Van Winkle, it would be that he is a throwback to the sleepier times before the Revolution, a symbol of the apathy in the land before people became the bustling and engaged citizens of a democracy. Rip returns to his old ways of sitting on the bench outside the inn and regales people with his story of falling asleep for twenty years. The final impression is that Rip is unchanged, which highlights all the more thoroughly the way the world around him has energized and transformed itself. The narrator says this about Rip:

Having nothing to do at home, and being arrived at that happy age when a man can be idle with impunity, he took his place once more on the bench at the inn door, and was reverenced as one of the patriarchs of the village, and a chronicle of the old times “before the war.”

If the question means, however, what is Rip's final impression of all that has happened, he leave off on a happy note. He no longer has a bossy wife to contend with. He is past the age when anything is expected of him. He can idle away his life happily and without ambition, honored as a representative of a former time.