The Ultimate finger pick
From the video, what I understand from it is that this Ultimate Fingerpick is an alternative for finger picks and the standard flat plectrum. I don't really know how it replaces the standard plectrum but it is definitely a good alternative to acrylic nails. Some people are born with really soft nails (like me). And we often have to rely on acrylic nails. The common problem of gluing acrylic nails is the fungus growing under them. For musicians who play other instruments like piano aren't supposed to keep their fingernails long. So when they switch between their guitar and piano, it could be a problem. This ultimate finger picks definitely solves that.
As for my doubt regarding it being able to replace the flat picks, it is more because many people may already be used to holding the pick and play. The grip of the pick also provides the strength you need for fast alternate picking.
Yet, again I have never try and thus, I don't know how it feels like.