Having played a few hours now, I can say the game was worth it's money.
Overall handling is nice - Sound is not getting on my nerves and the music fits in well.
However... It seems like there is literaly nobody playing the game online on Steam. I've been waiting in an empty Quick Match Lobby for like two hours without a single player joining in.
Also the game is... well... take a "fast" car, like the F-90 or the Mirage, and still every AI player will stick on your tail, keep up without problems and boost-slingshot past you all the time.
Once you fall behind a few feet, it becomes kinda impossible to catch up.
I completed every GP on "hard" so far, but hardly have any reason to even try expert difficulty.