Comparing an M6 to a Cayman s is not fair , but an M6 with a V10 engine and 500 + Hp can beat the Cayman s with the 1 sec difference as listed below. Cayman S is indeed a fast car around the ring with just 300 some HP.

Cayman S 8.10
M6 E63 8.09
Porsche Gt3 8.03 ( This car has almost 100 Hp less)
911 Turbo 7.50

I think M6 should be compared to 911 Turbo , Hands down you know 911tt is better.

Cayman S vs E92 M3 , sure M3 is faster around the ring ,I have driven both cars and the driving experience of the Cayman S is more sports car like than the M , The M felt muted compared to E46 M3 i had.

My local dealer is building Cayman S cup cars and they have been lapping times similar to GT3 Cup cars. Now that's something as you know Gt3 Cup cars top of the pack of ALMS gt class.

M3 CSL should be compared to Gt3 RS , M3 :7.5 , Gt3rs: 7.47

X5 M times are phenominal and just shocking ......no debate here.

I am just saying, for as big and heavy as some of these cars are like the M6 and e92 M3, they lap the ring pretty damn fast.

I don't think comparing the M6, which is more of a performance/luxury 2+2 GT to the 911 is fair, regardless of horsepower. I am not trying to dog Porsche. I happen to really like the 911 and Cayman. I just think that for BMW to rival or beat some of the Porsches times while maintaining their true sports sedan/coupe 2+2 status is pretty impressive.

I agree, that's a good point. That's what a i love about BMW's its a good combination of power and luxury.

X5 3.0i < base
X5 4.4i < S
X5.4.6is > S
X5.4.8is < GTS
X5 M > Turbo
(feel free to correct me)

I still love BMW's

IMO you're close but if you haven't had the opportunity to test them, see my thoughts at post #73.

Is the 4.4 you had above the 2004 4.4 with 315 Hp engine?

chilliwilli definitely agree on your post... it's all experience relative to what you have driven and how much experience one has of driving the beast.

vbmwx5: yea i was refering to the facelift N62 engine. the old m62 platform which i have and love; won't stand a chance unless Dinan has something to do with it ;)

After spending the last week driving a Cayenne S (it was a loaner and the Transsyberia special in particular), I'd take the X any time unless I was heading seriously off road. Even on gravel roads the X is better. If you want what the Cayenne can deliver as an on and off-road vehicle, buy a Touareg and save some bucks. And yes, I know the engines are different.

Interesting, what X do you have?

I have a 2005 3.0d but I've driven the 4.4 (both pre- and post-update) extensively. Also the 4.6is and the 4.8is. But for me it's not a question of the engines and I have no complaints about any of the Cayenne's various under-bonnet offerings. Here in Oz we get the V6, the atmo V8 in two states of tune and the twin-turbo V8 in two states of tune. We also get the Cayenne diesel.
In producing a vehicle that has genuine off-road ability, I feel that Porsche has compromised the Cayenne's on-road feel. Compared to the X it feels bigger, heavier and more cumbersome and the steering lacks the X's precision and feedback. All this varies of course with the respective tyre/wheel and suspension packages on offer (and the type of road surface). I'm sure that there are Cayenne fans/owners out there who would disagree, but that's just my two cents worth.
The other argument is that the Cayenne can perform off-road tricks that the X can only dream about so it's the better all-rounder. I just think that it's not as focussed as a road car.