Review
Reviewing the X6 40i and Cayenne Coupe - GLE Coupe was ruled out as the drive is the least engaging. My final pick is the X6 40i for the following reasons after comparing the "Standard" Cars for each make.

1) Price: price difference on both the standard cars is about $40k more with the Porsche. Do note that the "Standard" Car for the X6 is relatively well equipped (see 4 below)

2) Drive: X6 is comparable with Cayenne Coupe with both being engaging and seamless gearbox.

3) Looks: this area is highly subjective and whilst IMO both are equally attractive, I find that the X6 with the standard M Sport body kit has a more aggressive look and road presence.

4) Standard features: whilst the Cayenne Coupe comes standard with PASM and Sports Chronos, many other features are add-ons which is typical Porsche. The panoramic roof on the Cayenne Coupe gives nice lighting into the car but it is fixed and cannot be opened. The adaptive air suspension on the X6 is about right for me - not too harsh like the M-suspension and when put into Sports mode, is sufficiently firm and planted. Many other features are standard in the X6 including the M Sport exhaust system - the PSE is a $12k option...

5) Interior / cargo space: front / rear space comparable for both although the Cayenne Coupe felt a little less claustrophobic with the panoramic roof. But then again, if head space is a concern, a X5 or Cayenne would be a better bet. Cargo space looks the same to me although on paper, X6 has a larger volume. The new PCM together with the dash layout adds a fresher look and feel on the Cayenne Coupe but in terms of the usability, I will still lean towards to iDrive system.

What I do not like
Would have thought that the panoramic roof should be a standard.