I didn't mention it because I hate to beat a dead horse, but of all the navigation programs available, Co-Pilot is probably the worst. When you compare it, its accuracy, routing and address database, to Streets & Trips, Rand McNally, Tom Tom, Garmin, any of them, Co-Pilot comes up way short. You should compare Co-Pilot and PC Miler side-by-side, you'll be shocked, especially since both products are from the same company.
Since most GPS units and mapping programs use essentially the same mapping data, there will be locations that none of them can find. Can't find it on the Garmin, so Streets & Trips or MapPoint or MapQuest won't find it, either. But, Google can often find it. And with the Droid come Google Navigator, where you can tell it to "Navigate to: business name, city, state" and more often than not it'll find it. You can scroll through the navigation and even see the Google Street View picture of the destination.
But even if you don't want to use the phone as the navigation device, it will tell you where the location is, so that if nothing else you can find that same location on the map on the Garmin and tell it to go there, then let the Garmin take over. I've done that several times, it's really come in handy.
Add to that the Google Earth app you can download (free) and you have a powerful tool to supplement your standalone GPS unit.
