I drive semi truck, and yes, do use both with GPS in both programs. In fact, I have just purchased both of the 2009 versions. I use Streets & Trips 98% of the time as it is far more accurate on street addresses. If Streets & Trips can't find what I'm looking for, I will check the DeLorme program. That OCCASIONALLY has the address the other doesn't, but it's very rare. Another feature I like very much is that Streets & Trips will keep North at the top of the screen, and DeLorme is constantly rotating the screen according to the driving direction. That drives this truck driver crazy..., but some people like it that way. I update my software every year when they update, and did not like the S&T 2008 version at all, but the 2009 version seems to be working very well so far. That's my humble opinion, and only worth 2 cents... in this depreciating economy.