Most of the time I find MapSource to be adequate,however,for extra detail I use N.G. Topo to get some more detail.Sometimes I find that a Satallite picture is necessary.For "Geocaching" I find MapSource fills my needs.When I am out looking for petroglyphs I usually have a N.G. hardcopy with me.With N.G. at home I expand to get the cords.then enter in 76s.
Two Feathers