I have a bunch of large files in this directory, can I delete these? If I delete these, will they be re-downloaded (ever so slowly)? There's a total of about 15.5 GB in the Map folder.

I'm talking about the disk space on my PC .. if I remove these from my PC, will the also automatically be removed form the watch (presumably next time I sync the watch with Garmin Express)? I'd have hoped that once they are installed they would stay on the watch, but I'm not sure how this mechanism is set up.