The Thule XLarge box is not easy to load as top does not open up enough to have access for larger items. The support arms at each end that support the top in an open position are fragile. The ball joints at the top of the arms repeatedly separate from the plastic sockets and must be forced back into position. On a positive note the box is aerodynamic and I have not heard any wind noises at high speeds. Be careful of the extended height with the box mounted on top.
Great Storage... Latch Issues
Crossbars went on relatively easy to roof rails and was box installation was simple. Ribbing on bottom of box keeps it rigid despite load. Decrease of fuel consumption of about 20%. When fully loaded the left side was difficult to lock. May have overloaded the 165 lbs and caused some deformation. Considering using a tie strap to cinch it closed next time since there are 3 locks and I can only squeeze two and turn the key. Right side works much better. Good that it's ambidextrous. Latch issues.