If I had 1€ for everytime I either lost a thread adapter or I couldn't get one out because it didn't have cutouts... I'd buy a bunch more of these, haha.
Seriously though - the double cutouts are an absolute lifesaver, you can unscrew it with a coin, a pair of scissors or the back of a knife and it doesn't matter how you screwed it in, the cutout it always there. Such a simple thing, but so effective.