hvyhitter19,
http://www.delorme.com/topousa/default.asp
is the site for v 4.0 and it has the capabilty to download and view 10 meter photos of the area. Landnet photos go down to 1 meter. I didn't check out Terrafly but I believe they have 2 meter photo resolution. Now if you want the ability to print out large custom maps then I'd say that makes sense to go with the 49.99 version and 1 geographical area.
If you are also using a GPS then it makes sense as well. but if you are looking at it from the topo map point of view they use pretty much the same quadrangles (USGS) as you can buy from the state you live in or any number of sites.
I have not sean any difference in maps from several sites when comparing areas I know. Photos are a little different as to when the last set was taken and those dates are shown on the different servers with the photo information.
Greg
"Getting close to the game is the joy of Bowhunting for me, the harvest is a bonus."

Live 15 ft Python after eating a small Antelope!