Installation instructions left a little to be desired, but figured it out. Mounts solidly to roof, no whistling, but not "whisper quiet". You hear some wind noise, which isn't obnoxious, but the light sound of thundering/turbulence was much more pronounced than without a roof rack. I took it off and will put on when I need to transport something. Overall like the look & fit, but not as quiet as I had hoped.
2013 audi a4