Interesting comparison indeed, but I can understand why. It's a comparison of mis-fits, two odd-balls, two outcasts who've been injected with Performance Enhancing Substances to try and elevate their appeal.
I've never really been a Porsche fan, but I am very slowly warming up to the Panamera (rear's still a problem, as is the center console layout). It's performance credentials are without question very impressive, and it does have the ability to seat a 3rd and 4th person without looking as hideous as the Cayenne.
On the other hand, there is the X6M isn't thaaaat bad when you really take time to digest it's shape. Similar to the Porsche, the BMW has impressive performance capabilities, not just in a straight-line, but from what I've read it's a true M-car around the track. So both cars have more than enough performance for me, but cars have a certain level of quirky uniqueness about them..but my choice would be the X6M because I really like it's interior setup, especially the center console layout...and also the higher driving position makes it a much more enjoyable cruiser for everyday and long-haul use.
Give me the X6M either in Blue...or that Ferrari Red that we've seen in some of the press photos.
Still searching for the sense of it… 
