If you’ve got money to burn, you can look at the petrol engines without keeping one eye on the frightening running costs. The Cayenne S is powered by a V6 petrol engine that produces 414bhp, and which can get you swiftly from rest to 62mph in 5.5 seconds. The bigger Turbo model benefits from a V8 4.8-litre all-action engine that covers the same distance in 4.5 seconds before maxing out at 155mph.
The GTS will probably be more palatable to most buyers, however. It packs 434bhp, and can do 0-62 in 5.2 seconds. It also comes with a sports exhaust that emits an exciting note.
In terms of how it drives, there is barely anybody leans while four-wheel-drive helps with composure. It’s comfortable on winding roads, and if you want to enhance the experience you can choose from a number of optional extras.
Running costs are an area of weakness, with even the diesels struggling. The Diesel S returns 35.3mpg at best, and emits over 200g/km of CO2.
Even the entry-level diesel struggles, and can only average 42.8mpg economy.
The petrols are significantly thirstier, with the Cayenne S returning just under 30mpg, while, the Porsche Cayenne GTS returns 28.8mpg.
Inside, the Cayenne is well-appointed, and there are a number of luxurious touches. The dash wraps around the driver to continue with the sports car feel, the leather seats are supportive and comfortable, and the switches are exquisitely made.
It’s a lot more car-like than some rivals, but it feels as well-built as a proper SUV. Moreover, it’s practical. It might not have the option of a third row of seats like the Mercedes, but five adults are well accommodated for. The Cayenne is longer than last time, the rear seats can slide back and forwards, and headroom is good.
The boot, meanwhile, measures 670-litres with all the seats up. Fold them down and you can extend it to 1,728. The boot sports a wide opening and its load lip is smooth.
Price:
Mercedes – £104,900
Porsche – £53,900 – £121,500