I have a dodge diesel HD truck w/NAV and its far superior. It's never lead me through parking lots or wait until it was too late to turn. Also had Lincoln and it too was better than the BMW.
I'm not basing opinion on screen size or appearance but functionality. There is no excuse for being second rate at navigation, it's been out and available for many years. There are much better systems and technology than what BMW is using and that's what irritates me. I am truly disappointed at BMW for this.