sunroof / rack
I put the front cross bar just behind the sunroof opening to lessen the wind noise with the sunroof open. With the bars only, you can enjoy the sunroof, but when you add carriers, especially the sup taxi, wind noise is bad enough that you have to keep the cover closed at highway speeds. This would be a major downside to the Q5, as it only has a mesh cover with no sound insulation.
Another issue is that the roof antenna is tall enough it could interfere with kayaks/canoes unles the carrier lifts them up a bit.