Been using that for several years and a great way to mark points of interest or even tracks. We had a local reservoir drawn down about 30' while they were working on the dam and they added 30-50 rock piles for structure. Was able to use the Google Earth history and marked all the rockpiles along with some other structure and then transfer them to my unit. My first trip to the CA Delta, I created tracks and waypoints to find my way around. Might need a 3rd party software in some cases to convert to your particular format. I use GPSBabel which is free software.

GPSBabel: convert, upload, download data from GPS and Map programs