I can read some limited German, but trusted Google for this overview of the 4 major German magazines (same article to come in French later on). I hope there won't be too many mistakes!
First of all, I have selected a comment related to the transmission:
The automatic gear changes are performed quickly and smoothly. The driver has at any time the opportunity to change gears manually through the two paddles on the steering wheel. The resistance to the rocker is noticeably larger than for comparable systems.
Then a few words about the chassis:
The Brake Steer helps, but does not diminish the fun. The razor-sharp steering and active suspension work perfectly together.
And the conclusion!
No doubt: The McLaren has the necessary tools for class leader.
I couldn't put it through Google translator unfortunately, so I wil focus on the final comments of the article, which gives very positive words on the handling, mentioning neutral handling and the surprising but not too disappointing lack of limited slip differential.
I did not find much in the article, just a remark on the design which is focused on efficiency rather than beauty.
A very positive conclusion for this first drive:
Ferrari are loud, bright, poisonous. Lamborghini are evil, brutal, uncompromising. Porsche are minimalist, curve-hugging race track addictive. The McLaren MP4-12 is a racer for all days, with a GT sports car genes.