If you want a good solid thrilling FPS, do yourself a favor and pick up Rage.
This isn't to say the game is not worth playing. It is. This game combines great FPS fighting, and decent racing. I love the fact that cars and weapons are upgradeable, the fact that different enemies have different fighting styles, and i can't say enough about the visuals. Although a little tough even on easy mode, this title is one hell of a thrill. My biggest gripe is that things can seem a tad repetetive, but there's just so much else about this game that's good that you find yourself not caring.
If you like a good thriller, enjoy guns, and want something a little different from other post apocalyptic games out there, i highly recommend you spend the money and pick up Rage.