As I said earlier in the post: with opinions and a**holes, everyone has one!
Taste is in the eye of the beholder. I now have a new X5d and also drive a Panamera which shares the interior with the Cayenne. Both are extremely luxurious and refined in different ways. The Porsches have a very rich looking interior with great overall displays and high quality components. I would say that the BMW has a sportier look - Tag Heuer watch vs the Porsche look of a Zenith watch --- both great looking but in different ways.
I looked at the VW and the interior is not even close to either of the above. The Audi is very sporty looking but I have never been a fan of the display lighting which seems to "scream" at you. The new ML is quite refined and very luxurious inside. To continue with my watch analogy it is Rolex (a bit stuffy!).
Outside looks are also highly subjective. With the exception of the VW which is really not in this category (MB, X5, Cayenne) - all of these have their attraction depending on what is appealing to you. I must say that each of these looks very different depending on the color, wheels, and other minor mods (running boards, fender flares, etc). I would think that everyone has turned their head at one point or another at each of these on the road depending on these variables and how pleasing they are to the eye.
I think all of these have pluses and negatives when it comes to maintenance costs, reliability, etc, etc. I have owned MB, Lexus, Volvos, Porsches, Toyotas, Hondas, and a GM Yukon. Most of cars have been driving well over 100K miles each and some up to 240K miles. Interestingly the most reliable of all of these was my Yukon which I drove for over 175K miles and NEVER had a major mechanical issue. Had ONE set of brakes done. The only thing that went out was the AC at 150K miles. With all due respect to Consumer Affairs, their evaluations are less than accurate and this is just not for automobiles.
All of these are fun to drive and again depends on what you are looking for. The X5d to me offers a great deal of power on demand with excellent MPG. That is why I just took delivery of one - premium package, seat package, sports activity package and running boards. In my opinion a great combination of value, looks, fun to drive, etc, etc.
As I said earlier if acquisition $$ and expected cost of maintenance were not an issue I would buy a Cayenne Turbo fully loaded ($100K plus!). But when the novelty and excitement of the purchase wears off and the reality of the cost sets in for the average buyer this would be a very exorbitant purchase.
Read my first line on this post again!