Need help deciding between the X5 xDrive40i and the Audi Q7 3.0T Quattro

I'm torn between purchasing a BMW X5 xDrive40i and an Audi Q7 3.0T Quattro. Both vehicles seem to offer impressive performance, comfort, and technology features. I'd love to hear from fellow BMW enthusiasts about their experiences with these models, particularly in terms of handling, reliability, and overall ownership costs.