Before we start I am Not biased towards either car. I sell Lexus for a living & I am a driving enthusiast. The TSX is a MUCH sportier car, It Is lighter , more nimble, offers more feedback through the tires and wheels and is much flatter overall. The car is starting to look a bit dated and is long in the tooth needing a new model .The C300 Is a Great LOOKING car in my opinion, Even the standard cabin with the "TEX" seats (Leather is not standard) Unfortunately the throttle is jumpy, the car suffers from tremendous body roll , the steering has a vague on center feel and the car feels like its on marbles. Also with the standard motor it cant get out of its own way. It does have the benefit of All Wheel Drive. The C350 adresses many of these problems and Its hard to believe the C63 with Its Obsene preformace shares even a single componant with the C300 Sport. Its Jekyl & Hyde. If I needed a sports car and was worried about handeling and Fun I'd pick the TSX... If I was Purchasing a sedan for my daily commute I'd pick the Benz