I am a user of iguidance 4.0. I find the program relatively easy to use and navigate but the interface is substandard to Garmin. One feature I found very nice on my Garmin Nuvi is that in regular driving mode (not routing anywhere), the approaching cross-street would be displayed on the top bar of the screen. I notice that iguidance displays the street you are currently on (not too helpful since you know you turned onto that street), but does NOTHING to highlight the upcoming street like Garmin does.
I am looking for carpc GPS software that can display the approaching street like a Garmin. (I am currently using roadrunner as my frontend but will gladly change over to one that supports a gps software using this desired feature).