Originally Posted by Onebyone

Using one eliminates the repetitive motion using scissors or snips which is very bad for your hands. You aren't using your hand to cut, only holding the fabric.
I have seen the ones made with a seam ripper sticking up and they are dangerous. A guild member went the cheap way and got impaled for it. LOL If you have an unused thread cutter pendant, that is safer to stick in a piece of wood or spool.
I have seen two sizes, short and tall. I like the tall one the best. They aren't that expensive.