Keep gupdate.gcd on-board after update?

[Butters]

Too busy having a go at you and forgot about why to use RGN instead of GCD. I did kinda answer that before, Posts #4 & #8:

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• I don't know the 'how' of device being triggered to use the GCD file other than it recognizes that the file is for a different version firmware than the one already loaded. The GCD itself is a bit like a self-loading EXE file, simplistically, in that it contains the same data as an RGN file and additionally (I suppose) a 'header' that directs loading of the new data to the appropriate regions.
• RGN files are a 'stripped-down' version of a GCD and must be loaded manually in preboot mode using Updater.exe.

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............ what do I do next to update the unit? Do I have to convert it to .rgn and use Updater.exe? Or can I update the .gcd file directory by just putting it under Garmin directory and reboot? Which method is "safer?"

Using a safely-named RGN and Updater.exe is less risky than using a GCD imho.

To expand that, the reason it's less risky to use an RGN (if it's safely named <HWID>01000<SWV>) is that a corrupt GCD will 'brick' the device, it's easy enough to fix when you know how: use Cure fw to get MSM back. i.e. Load cure fw, delete GCD in mass storage mode and then load original fw. Easy Peasy, but uninformed users freak out big-time. GarminExpress loaded a lot of bad gupdate.gcd files in it's early days. Garmin blamed users disconnecting while updating of course.