Magic Tricks

The pen works as advertised, and the gimmick is well-designed and visually undetectable. I had no concerns about my participants discovering the secret.

The main advantage of the pen, the entire selling point really, is that the participant un-gimmicks the pen herself without the magician touching the prop. This "proves" that the pen is normal, and it is convincing.

Two drawbacks.

First, the pen must begin in a gimmicked state, which means you can't openly use it to write prior to the secret work. This is contra the design of most effects, where the proving happens before the dirty work, not after. This drawback can be mitigated through some subtleties, but nevertheless purchasers should be aware of the limitation.

Second, the reset is a hassle. It can't be done openly and there's a (small) chance of losing track of the gimmick during the operation due to human error. Three gimmicks are supplied, I suspect, in anticipation of this eventuality. By contrast, routines using a simple pen s****h have the luxury of an instant reset.

In sum, you are purchasing a well-made convincer. For me, simply using two pens remains the more practical option in most circumstances.