Definitely one of my all time favorites. This is the racing game to have, no doubt...great gameplay/controls...ride it!
The tracks are designed well and modelled after the real ones nicely. Seca feels like the real thing (aside from crashing of course). I personally don't care much about the customization but it does add to the game. Playing this game online is what makes it even more fun...aside from the usual lag issues the game plays well; I'm still playing online.
Can't wait for the next instalment!