There are lots of compromised in the spec. Like 4 hours at 3 seconds per shot. I don't thnk many accidents take 3 seconds.
I saw one last year that had front and rear facing cameras.
This does not say how it stores pictures but what it should do is record in a loop so you store the last, say, 30 mins at decent speed then if you need to, press STOP and you have the last 30 mins and never run out of storage.