I have CRC and have played through the championship. It is a far better game than the forums at BHMS would have you believe - sometimes people in the hardcore sim world can be a little snobbish A lot of the opinion is based on the 2nd demo which has a number of bugs which have since been addressed in a patch. They really should release a new demo as it doing the game a lot of harm.
The physics, while not up to the standard of, say, Richard Burns Rally, are quite acceptable and enable you to to have a great deal of fun with the cars. For example, the car handling is better than the latest iterations of Colin McRae Rally or Xpand Rally....IMO.
There are 5 main maps (with many different configurations per map) including, mud, snow and ice, tarmac and a beach track. The AI are a bit dodgy and annoyingly aggressive at times. With practice they are not too hard to beat especially if you can break away from the pack.
MP holds great promise although there seems to be no one online at present - I'm hoping this is because it's only been released in Europe so far (or so I believe).
As an added bonus, if you have TrackIR, it has the best support I have seen in a racing title yet. Don't ask me what they have done better, but whatever it is, it enhances the driveability noticeably. It also supports TrackIR Vector Expansion which means you can lean from side to side, backwards or forwards and even sit up to see over the dash. In a hairpin for example, you can not only glance sideways at the apex, but also lean forward and sideways in order to see around the door pillar. It's very cool when you see it