Basicly its a lightweight version of the M3. Carbon bodyparts to reduce weight, I believe it also has more power, better handling, semi-slick tyres(as far as I know), has no A/C unit (might be optional).
i was kinda suprise as like many of us thought the stock rb20 and 25 turbines were bushing turbo's but they are actually ball bearing ceramics... i just found out when i dismental my turbo and found bearing in them...