I picked this up over a year ago and still love it. It's absolutely worth having in the arsenal.
If you already use double blank cards definitely take a look at this. It's not going to replace a
CT and it's not meant to. The first time I thought to use this I was surrounded, and it was the
perfect tool in that moment. I originally dismissed this, but opinions I trust kept recommending
it. Try it out in front of a mirror for half an hour and you have it forever. Not much of a
downside imo. Your mileage may vary of course.
Good luck.