I was disappointed in it - it didn't look much better than CMR2 on a decent PC. It drove okay, but wasn't a big leap - I think WRC drives better. I would recommend waiting for WRC II - from the pre-release interviews I've read they seemed to take much of the criticism of the game seriously (and to be honest, the only real fault of the game was that it was too easy) and have worked hard on the driving model - it's meant to be from the same code as the basis of the Prodrive Subaru simulator - so that and official licenses have got to worth a bit.
I would recommend waiting.