Great idea, lousy implementation
I'll start with the bad things to finish on a positive note.
Graphics: The opening sequence is excellent but the in game grahics are poor to say the least. I've seen better on the PS2 to be honest. One of the first track you race has a muddy wet bit but has got to be the worst bit of graphic display I've seen on the PS3. Oh yeah and the framerate is distractingly poor in places.
Gameplay: Controls are horrible and the vehicles feel very unresponsive. The AI can knock you off line by looking at you and yet stay frustratingly in tact even when you ram them. This makes even the opening round on "easy" to be quite tough to beat.
On the positive side it's a great idea with plenty of customization options for the vehicles and looks like being a lengthy title to complete. However there are many better titles for the genre on the market with more on the way so do what I did and RENT IT FIRST!!