It took me a while to beat Darius with my Lamborghini Gallardo but you would probably have a better chance with the Subaru Impreza......but if you have enough money, you should most definitely buy the Mitsubishi Lancer....this tuner car, which you most likely know, is great in handling and is pretty fast for a tuner.
Bottom line, you should use the Impreza, and if not the Lancer. Trust me.