When I ordered my car I went with the NAV system and it's awesome. Agreed that a touch screen would be easier to use than the knobs of the BMW system, but it's pretty easy once you've used it a few times. Nothing agains aftermarket units, but you just can't recreate the look the cockpit has with the OEM unit. I think it takes the look of the interior to a whole new level. Plus, you get the James Bond-like flip down screen that hides the CD slot. People always freak when they see that in action.