Here's my Hannibal roofrack with the side bars and tent removed - it's on its way to be powder-coated.
The sunroof opens without hitting the rack. The view of the underside of the rack is not too inspiring.
No noise from this rack, even with the tent on there, as long as the sunroof is closed. With the sunroof open, its like a hurricane.
I tried all the Yakima and Thule stuff - still have the dimples in the roof to prove it. Hannibal is the way to go if you regularly put stuff on the roof. I got mine from Rover Accessories in LA.