I prefer DeLorme's Street Atlas and Earthmate GPS units. I used their software initially starting in 2000, then I switched to Microsoft's Streets and trips around 2004. I found it lacking in functionality and usability. So, I switched back last year to DeLorme's solution.
The thing is, both Microsoft and DeLorme add new stuff/options to their software every year in the attempt to keep ahead of the other so you almost have to try both packages every year to see which you might prefer. For me, though, I have always preferred DeLorme's interface and usability over Streets and Trips.