This is a better game than you may have been led to believe; especially if you enjoy crashing for points and driving hum-dingers. It is overpriced, so get it on sale if possible.
All of the single-player modes are solid. The demolition derby modes offer particularly realistic AI drivers (similar to IRL experiences at the derbies of my youth). Knock Out
mode is great fun—it reminds me of platform-based fighters and the joy of knocking someone off the edge—except if you fall with them, you can keep jumping back up.
skills from DiRT 3 are not a prerequisite but will carry over in this game's trick-oriented modes. Learning those maneuvers early on in either game makes them much more enjoyable. Joyride
[main menu] offers tutorial missions that are a great (not so obvious) way to master them.