It's quite the simulator you don't expect it to be
It took me a couple of hours to accommodate with the analogical controls (didn't played on XBOX before) but when I was still learning I loved the game.
It gives you the sensation you are really participating in the race. Everything you do (brake late, acc. early, etc.) has an effect on the car and on its handling.
The cars are lovely modeled. Performance and design. I was disappointed in a few cars that in reality perform much better (I'm speaking of acceleration and top speed, handling is good overall) than in the game. But other than that you get 10's of hours of play time. If you have anger problems maybe you should get a couple more controllers for backup. Half way through the game and the AI really picks up the pace.
It is truly a masterpiece.