Seriously, if you're a fan of arcade racers in general, the PC version that just got released is unmissable. Not only the best kart racer I've ever played, but the most fun I've had with a racing game since Split/Second.
Plus, it looks GORGEOUS. Like, this would have been impressive as a CGI intro-video to any racer from the last generation. Runs like a dream too. Cannot recommend the game enough - and it's only £13.50 from GreenManGaming if you use a voucher.