I've seen the video already, it's a cool concept a great piece of creativity, but I would still just use my bow.
If you really need a small ranged weapon for your bug out bag, a slingshot should work well. And it's alot cheaper than this survival flippehr

But you do need to practice these weapons ofcourse, don't simply put them in your bob and expect to be safe.. it takes time and skill

eh, it looks like they tried to reinvent the wheel and failed. Cool idea for a fun toy but that is about it.