From my playing around with Google Maps (3 yr old Android device), it is improving all of the time and nothing is as accurate - jespecially for free. You can now log on to the Google Maps web page using your computer (with your Gmail account if you have one) and map out your desired route, then you can highlight the route and save the map to your account. Then when you open the Google Map application on your phone and sync it with your Gmail account, your maps will be available under My Saved Maps. Great for planning scenic drive-focused trips.
I like being able to make my own routes using back roads, instead of the shortest, fastest type of routing that standard Navigation (satnav) units give you. Also, being able to choose said routes with the full function of a computer, mouse and keyboard make it much less frustrating than fat-fingering my way through the process on my phone.
Obviously the lack of weatherproofing on a phone is an inherent risk. But this option is far easier to upgrade in the future.
