I am really found of Imagine simulation sceneries and sorry if they get the "Worst website" award from AirdailyX. I am not worried for them, they have good competitors on this matter.
What is worrying me, is this new habit, which consists to deliver a small upgrade just to update the official release date (or maybe is it just the webshop's mistake ?).
Washington Dulles KIAD was not released on 12/13 december 2010. Sorry. I bought my copy in august 2010 and it was definitely not even a "fresh" fruit at that time. And about this 1 megabytes upgrade, there is strictly no information on what have been improved. Imagine Sim team have top priority to answer this post. Mistakes happen.