RoadTrip for Mac users is quantum leap over trying to use the old MapSource for the PC. The interface is very Mac-like and was apparently developed by experienced Mac developers rather than being a clunky port from the PC version. It does exactly what it is intended to do without a lot of extraneous bells and whistles. It works very well with the newer Garmin USB compatible hardware and transfers data at very good rates. It gives you the ability to store copies of your trips and download a variety of more detailed mapping information to your GPS. Although it only works with the newer USB Garmin devices, if you have one of the older Garmin devices with a serial connection, you can still use RoadTrip to create routes and review tracks if you use a utility like Hiketech's Link2GPS and GPSWrite for connecting your GPS and transferring the data. If you are an avid or even casual GPS user who wants to go beyond what can be done with portable devices alone (i.e., enter a destination address and say "take me there"), then I highly recommend that you try RoadTrip.