Seeing both on the road - I prefer the 911 by quite a bit. The Jag looks pretty cool, but the 911 is very distinctive and looks more like a more well integrated package. The Jag has some of the problem that the GT-R has in that non-enthusiasts looks and think "not sure what that is..."
And this might sound nuts, but I have to think the build quality on the 911 will be vastly superior to the Jag. Not sure if that's true, but it's my gut feeling.
The GT-R does absolutely nothing for me. I know it's quick and fast and a performance monster, but I've never warmed to the styling and after spending time on the track with the new Miata, I know I certainly don't need the fastest, highest-performance machine out there.
It's become clear that I desire a driving experience that's more visceral than overly calculated.
I've been an obsessive Porsche fan since childhood. I went into this test with a barely contained bias, but that Jag won me over.
At one point, on our drive back to the city, Jonathan and I passed a school bus full of kids on the highway. He was in the Porsche and I watched as he passed them, and none of the kids gave the 911 a second look. As I pulled along side the bus, I noticed several excited faces pressed to the windows. Naturally I felt obliged to pace the bus for a moment, turn on the loud pipes button and give the kiddies a concert from the Jaguar's quad pipes.
A car like this is supposed to be FUN. It's supposed to make you grin maniacally every time you drive it. The Porsche is brilliant, but the Jag is the car of passion.
Oh, and as for quality.. if I recall correctly, both had minor interior 'glitches' despite their price.