This X5 3.0 is simply the best handling SUV among all the ones I have owned and test-driven. I picked 3.0 over 4.8 because (a) to save $8-9K, (b) 3.0 engine felt smoother in lower gears and is adequate for our purpose, and (c) for a SUV, handling is more important than performance; we'll save the performance for our sedan.
iDrive - once you get used to it - makes the most sense. Don't need to reach for rows of buttons and dials while you drive. Practical everything is under your command without moving your hand away from a single control. If you can learn to use a Wii Nunchuk, you can learn to use the iDrive.
The ride maybe a bit firm for some. The price a bit stiff as well.