Originally Posted by e92law

There must have been something wrong with that X5 35d you rode in. I just picked mine up on Saturday and it is incredibly smooth and quiet at idle and while cruising. Only lets out a little diesel chatter at large throttle openings.

I actually drove it from LA to Phoenix on Monday, set the cruise for 90 (yes, I know not allowed according to break-in rules) and averaged 24mpg. It was incredibly smooth. I am actually also stepping out of a tuned 335i that didn't get 24mpg set at a 90mph cruise. That being said, I will certainly miss the insane acceleration, even above 80mph.