I have never owned one such knife, but the video makes it look like an extremely dangerous closing mechanism.
You have to press a button below the cutting edge to close it? I sure hope it has a blocking mechanism that prevents the blade from closing fully until the finger has been completely removed. Like a timed spring or something, and even that sounds like a laughably bad idea.
Now, that is what I have gathered from the video only, it might very well just be a bad illustration of the mechanism.