We're taking a trip to Ireland this summer, and we can get a GPS with our rental car for a fee. But what if we just bought one here, so we could have it to use at home, and took it with us on the trip? I've found one GPS unit that says it comes pre-loaded with maps of the U.S., Canada, and Europe. If you buy another unit, can you just download the maps to it?
How does this work??