Braking is well controlled and easy to modulate with the Porsche and the six speed automatic transmission works well. I would say it corners on a par with the Infiniti FX series, but has more room. Driving it is easy, what is difficult is holding it to the speed limit. Porsche knows this and has included a consumer awareness sticker that is unprecedented even in these political correct times. It simply informs you that with the mud and snow tires the Cayenne should not be driven above 150 mph. That much metal moving that rapidly is surely visible from space let alone a patrolman's radar gun so be warned.
Keeping with Porsche tradition, the ignition switch is on the left side of the steering wheel. The radio also has the same traditional look with an endless array of small station buttons that not only require you to remember which is which, but have fingers small enough to push just one. Every time I see this Porsche radio I remember the story about the Andre the Giant whose fingers were so large they did not fit into the holes on a rotary phone making it impossible for him to it. I have the same feeling when trying to use the Cayenne's unit.
Speaking of size, the Cadillac has 70 cubic feet of room with the middle row folded sort of flat which is better than the Porsche by a considerable amount despite the Cadillac's narrower body. Both cars fit easily into a garage and they can be parked without drama in any parking place not labeled compact.
Young working woman's view: These vehicles put the word sports in SUV and thus they most likely are going to require a period of adjustment to get used to driving. For example, the Cadillac does not have a lumbar adjustment or a power adjustable steering wheel and so I had a time finding a comfortable driving position. The optional DVD screen is controlled by the backseat crowd and they have wireless headphones meaning you have no idea what they are playing or listening too unless you carefully edit their choices. The Cadillac also has more intrusive ABS and less brake feel and took longer to stop. When cornering, the Porsche turns in right now, while the Cadillac is not so abrupt. It is easy to see that these cars truly reflect the fundamental goals of the company's that build them with the German Cayenne easily the sportier and the SLX more of a comfort giver.
You need to take a close look at Cadillac's option list. You can order it with two wheel drive only, which I would recommend if you don't need the traction of the all wheel drive system. You also save nearly $2000 plus getting better fuel mileage. If you desire the navigation system you need to see if Cadillac has changed their minds about only offering it with an extensive list of other options such as xenon headlights, all wheel drive, and magnetic ride control. These add up to over $7000 so check it out first. I didn't find the Cadillac DVD based navigation system that easy to master.
Despite having several suspension settings, the Porsche rides crisp all the time. It is a reassuring, solid type of feeling you get, but over rough roads it can become tiring. The SRX has coil springs and magnetic, automatically adjustably dampers that offer a more sedate ride quality.