Many years ago I remember taking a ride on a custom-designed vehicle (not a flying one --- don't recall exactly, it might've been a ground/water tour), and distinctly remember that they used regular automotive seatbelts --- there was a GM logo visible on them. Something like that would've been far easier to release in an emergency, whereas in this case it seems they used locking carabiners that take a considerable amount of time and fine motor skill to manipulate.