If I could order my E90 all over again, I would get iDrive again. No question.
IMO, it integrates very nicely into the car. I am a nav junkie
. As much as I like the portable units (I have some of them, too), and as much as I dislike the BMW nav interface, I think there is a tremendous benefit to having nav built into the car.
Besides nav, iDrive makes other things easier. The display is big and crisp and at eye level, making it easier to see and do things like adjust the radio station, read the full text of warning messages, check the oil level, adjust car settings, etc.