After 125 hours played:
this game is amazing, it feels very real, I play with analogic controls and have the traction control and ABS desactivated and after geting used to it and controling spins and braking lock ups the lap time is slightly improoved with respect to using driving assists. Despite tipical racing games F1 2013 doesn't feel arcade at all, other cars don't wait for you if you do a mistake (like in need for speed, gran turismo, GRID, etc) the radio comments are just fine, not annoying stupid things like in americanized racing games as Dirt 2. Damage simulation is not totally realistic, if you hit another car very softly nothing is broken, while in reality any contact will break some aerodinamic part of the car.
Have to say that I don't play video games since 6-7 years so obviously the graphics part looks like outstanding to me, even with a laptop graphics card (AMD Raedon HD8670M) the details, resolution and framerate are very good.
The sound is another strong aspect of the game, try to conect it to a good (powerfull) speaker or hifi system, and turn up the volume, the engine sound in the straight lines is astonishing.
In grand prix mode you can choose: 3 laps, 5 laps, 25% race, 50% race and 100% race.
I use to play 25% race, it lasts 20 minuts with 1 pit stop, managing the fuel maping is important, this strategycal aspect is one of the things that makes this game so realistic, pure race simulator no arcade game.
About lap times, they are quite similar to 2013 F1 season, maybe 1-2 second faster for a really good lap.
At the begining the full screen mode didn't work, just change fullscreen from "false" to "true" in some file and problem fixed. After some update of steam it stoped working, fixed downolading the last drivers for my ATI Radeon GPU.