I could never figure out why a lot of guys want to use a laptop and mapping software when highly functional and relatively cheap GPS units are out there that will mount in the windshield in ready view and are easy to operate with the touch of a finger. Plus, with "North Up" turned on it helps keep you better aware of your location orientation IMO. They use the same map database (Navteq) that the others use, plus have logging features and a multitude of other navigation related features. Save the laptop for radar, location plotting, and weather web page access. If you want a quick, broader view, paper maps never fail.
But honestly, if you're going to use a laptop (or better yet an apple Ipad) Google Maps app is hard to beat for accuracy and keeping up to date with new roads, without constant downloads, plus it has the added benefit of live traffic conditions across ALL well-traveled roads, it's fast and very efficient. And it's also hard to beat for easily finding anything you could ever need to find in terms of businesses. I'm not a fan of Google, but their Maps app is far superior to anything else out there and it's free. It's biggest drawback is when you are in the rare situation when cell data is unavailable but that's why a dedicated GPS navigation device pays for itself.