Shahano

Honestly I found the P1 the most disappointing. Not only does it have the best tires, it also has its own race mode that should give it an incredible amount of downforce. Very disappointing, I expected much better.
LaFerrari is my personal favorite, and the most impressive in my opinion.

For FYI, when I used to race F3, the F3 laptime around silverstone national was less than 53 seconds and that car only has 230 hp.. Shows the capability of downforce and slick tires.