Mine's positioned dead center, pointed straight up and there's no air space between the top of the antenna and the bottom of the spoiler. Held in place with IPass velcro which has amazing grip. And as you said, it now cuts out in places it never did before. Even in my own driveway when partially obscured by my tree. I have to wonder if being positioned at the leading edge of the roof is minimizing the ground plane. Or does that not have any effect on satelllite reception, like it does on cell antenna placement.

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'04 E53, 4.4 Sport
'97 E39 528i
'86 911 Carrera, track car
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