For the most part, the bag does the job. It is affordable and roomy. However, if your cargo is water sensitive (or you did not use poly bags to protect it) you'd better pray for no rain. Granted, waterproof might not have been stated as a product feature, but one would expect better protection than the bag offers. I got lots of water inside!
The tie-down points are oddly placed at only the front and back extremes of the bag, but nothing on the sides. This forced me to move the two crossbars of the roof rack all the way out and, thus, place the bag directly on the roof, so that I could tie down to the cross bars in the front and back of the bag. This is unacceptable, I thought. The bag should allow for placement ON the cross bars! Of course, this would have been a non-issue had they provided longer tie belts or, obviously, tie-down points on the sides of the bag.
The flap that covers the zipper (and helps for water leakage protection) is held down by pieces of Velcro. That is fine, in principle. However, the Velcro pieces a so small and far between, that the flap is invariably forced upwards by the wind forces, totally defeating its design purpose and, in fact, offering increased drag...