You are on the right track. $15 instead of $50 would be very attractive and small enough to attach to a keychain makes it an excellent travel option. I have cutters upon cutters but I also have a cheap punch that can go on a keychain so I always have one available.
I noticed the spinning when I had to use a toothpick or paper clip or something. There's maybe even a coating (eventually all the dried blood and bits of skin from all the stabbings will build up lol) you can put on to combat that.
You're on the right track. It's a different mouse trap, not saying it's better.
I am interested in one to replace my dollar store corn cob holder I have in my car. It's not pretty and has no cover. Keep going Michael.