ya until you have to buy parts for it. Which is like 10x's more expensive. Me and a buddy put long tube headers on his 06 GTO cost him under 400 brand new. Long tubes for ours are like 1500 and more.
The C300 is a piece of crap visually... it's only redeeming qualities in this case are the 8.3L, Tremec and Eibach parts.