I have G- sensor on too, but unsure if this kind of accident will be enough to trigger that, it is of course on maximum sensitivity.
Works like a charm on my DR though the G sensor of course then only save low bitrate footage as it cant change pace to regular settings, but that is also just fine the main thing is to have things locked in a safe place ( RO folder )
Using G sensor too if it have been triggered, also prevent having to look thru a lot of not interesting footage to find the event.
Okay my DR would not have detected it as i found out, with its "install" not to anything rigid, G forces cant really travel to the main unit to be detected, but drop a matchstick on the main unit and it is detected.
I think this need to be highlighted in the DR manual as some like me will not install it it rigid / to something rigid, mine is draped in the wires over the transmission tunnel in front of the gear leaver, some i assume will put it in the glove box and just have it "slide" around in there, even if the DR come with good mounting kit.