Bottom Line- Ultimate compromise between sport and luxury. Very quick, smooth, glides over nicks and crannies in the road. I spend plenty of time on the road- love the silent ride! On the contrary, when the pedal hits the mat, the engine makes an extremely defined roar. Comfortable as hell up front, not so in the back. If I was at the track every day, 335i would be my choice. If I needed a car that would accommodate my daily driving with comfort and performance- no brainer- IS350. Excellent Audio.