We'll have our first chance to use Global Entry this September, but we have friends who have used theirs and thought that it expedited the re-entry process significantly. Lines for both passport control and for customs can be quite long at Washington Dulles airport. The last time I re-entered, we moved fairly quickly throught passport control,picked up our bags, and then sat in a long line going through customs. I looked longingly at people whizzing by me in the Global Entry customs line, and we applied shortly thereafter. With respect to TSA Pre, on our last (domestic) flight at Dulles, the TSA Pre line was longer (I thought) than the regular line, but it moved much more quickly since it is almost exclusively experienced flyers who don't have to take off shoes, take out laptops, etc.