Like others here, I’ve had trouble when the GPS compass had lost calibration. You dont notice it until you try to use it.
Its very difficult to get an accurate bearing with a magnetic compass eg silva . Plus / minus 5 degrees is about it. Fine for navigation but can put you dozens of metres out at 300 m. Each degree error at 300m is 5.2m sideways. Perhaps a sighting compass would br better.
The back bearing to a piece of toilet paper or red ribbon is good (@micky duck) . Another method is to take a wide angle and a telephoto pic on your phone which can help.
Garmin sight n go does seem equivalent to “project waypoint”.
Note that if there is a big slope like > 20 deg the line of sight distance from your rangefinder will be greater than the horizontal distance on a paper map. Im not sure if the garmin software tries to allow for that or not. Make sure your rangefinder isnt on “true ballistic range” mode !
So its a good start but might not give good enough accuracy in difficult country.
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