I love the Nat Geo Trails Illustrated maps, have quite a collection of them and always have one in my saddlebags.
I guess I'm a map guy and while the Trails Illustrated maps give a great high level view being 1:63,000 scale, I tend to use the 1:24,000 USGS Topo's more when on the trail as it's easier to place myself (where am I) on the larger 1:24,000 scale maps.
If you have a GPS, and want to find where you are on the paper map, learn to use UTM, and, set the correct map datum. Usually, when I stop for a break, I get out the map, pick the point where I think I am, and then position myself using the GPS to see how accurate my estimate is. By doing this, I learn to use the map/gps combo before I really, really need it.
I have a mapping GPS (I actually carry two mapping GPS's along with a compass Garmin Etrex Legend HCx and a Garmin 60 CSx) but the 2 inch screen just leaves a lot to be desired IMO.
I've picked up a couple of Trails Illustrated maps to give as Christmas gifts to some of my other trail riding friends.
For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.