I have the X5 4.4 with sports chassis. My brother has the Cayenne Turbo.... and my preference goes to..... the X5 ! Maybe because it' s a bit smaller and around town the Peper is a pain in the a.. to park, not mentioning when going down small streets.
I admit the X5 being a ride a bit too rough because of the hard suspension and fat flat tires. The CT is much more powerfull for sure and feels more luxurious...
Just my 2R