So here's how it works. Once you take off from the airport, if you have an established course to a destination, you must get 8 miles away from your original airport before it will load the data for the new destination airport. Then it loads all of the freq that your GPS database has for that destination airport and you can easily select any of them to load into the radio. Very easy to use and a neat feature.

This is very different from how the SL30/SL40 work so if you've used those you will have to learn this new method.

In my case I'm using a Garmin 495 gps, I suspect that all of the newer Garmin handhelds will work. You select Aviation in / NMEA VHF OUT for the comunications setup on the GPS. You can also check the options under advanced setup, but I didn't have to change them. It's set at 9600 baud and works great.