I have an older version of the DeLorme Topo USA program and it was $100 with about 7 or 8 CDs. I think they now put it all on one DVD.

After looking at the maps, it sure looks like DeLorme just took 1:100K series maps to suit their purposes (similar to what Garmin did with their MapSource Topo program). The other scales 1:24K, etc., don't appear the same as USGS topos. Contour intervals appear to be guesstimated when less than 1:100K. The one thing DeLorme has going for it is the draw tools and routing tools have plenty of features and are easy to use. The 3D model option in is also pretty slick.

I also have the state version of National Geographic's Topo program. The maps are detailed and are scanned USGS topos. The draw tools and routing tools on the NG software leave a bit to be desired. Kinda clunky.

It would be great if they would combine the software of DeLorme Topo USA with the maps of NG Topo.