I'm using City Select 7.0 with a Vista C. I'm impressed with the autorouting but have found that sometimes the quickest most direct way is not necessarily the best way. For example, on the Rotary Trail cache in Waterville, the route chosen by the Vista C kept putting me on the wrong side of the river, which was obviously the closest point to the cache. Knowing the area helped so it wasn't a major issue. The issue would be an area I'm not familiar with. While the autorouting and maps are detailed the Vista C screen is small and doesn't give enough surrounding map to help in the situation described above. When you zoom out the maps lose the detail and when zooms in it only show about .75 miles squared.

The ole' laptop with its 15 inch screen is still my best mapping tool as I can see detailed maps of 20 miles squared.

How I digress, I like the City Select by Delormes, its powerful and relatively easy and intuitive to use. I would recommend it for caching but it does lack detail terrain info that the topo would have.