Hi Billy
The files recorded to the 'unsaved video' folder are each just 1 minute long - these are the ones that will be overwritten once you've reached your micro sd cards capacity.
If you instruct the dash cam to 'save video' via the voice command it saves a 3 minute video to the 'saved videos' folder. This saved video seems to cover a period from both before & after the voice command & because it's in the saved videos folder it won't be overwritten if your card is full.
I've been using the Garmin 55 for approx. a month now & have to say, with one reservation, I'm very impressed. It's my first dash cam, but have dabbled with my father-in-laws Next Base & whilst the footage is probably similar, the file structure for the Next Base when connected to a computer is terrible.
The one reservation I have being the unsolicited recordings it can make when the dash cam obviously thinks you've instructed it via voice command but you were in fact chatting to someone else in the car or it's picked up something off the radio. This seems to happen quite frequently & it would be good if Garmin could fix this via a firmware update - making sure the dash cam has to have a very definite 'OK Garmin' command before it decides to react. You can switch off voice command, but I see this as a very useful feature as I assume the alternative would involve having to pull over & press various buttons to save a section of video? So, I keep voice command on & just re-format the memory card quite frequently to get rid of the unwanted saved files.
Hope this helps
Dash