I just returned from a vacation, so I don't have much time to post a lot of details or pictures but I can do that later on at your individual request.
Only one thing: 997 Turbo Tiptronic, 15000 km on the speedo, full fuel tank, one person in car (driver), somehow "controlled" conditions (same temperature around 16* Celsius, same track/Autobahn, several runs) and the external Performancebox GPS antenna which by the way seems to do fine even at speeds slightly over 300 kph (manufacturer guarantees 180 kph only). Why I mention the GPS antenna? Because using the internal Performancebox GPS antenna, I had two times a very short GPS signal interruption which renders the test result pretty much useless. You need a COMPLETELY clear view to the sky to all directions when using the internal antenna, otherwise the results aren't accurate. Just as a little reminder.

Here are the results of the tested car (1620 kg weight):

Power at wheels: 357 kW or 486 HP
Max. lat. accel.: 1.1 G (Michelin Cup)
0-100 kph: 3.9 sec
0-200 kph: 11.1 sec
0-250 kph: 18.0 sec
0-300 kph: 32.1 sec

Please note that I was NOT using the brake/throttle method to accelerate from standstill to avoid too much stress to the drivetrain/tranny. With a brutal brake/throttle acceleration, I think that it would be possible to shave off 0.3 to 0.5 seconds off the time I posted, especially from 0-100 kph.