I prefer this to the wrist watch version for the simple reason that with the watch you have to take it off and on your wrist.
With this you just take it out of your waist coat pocket. (assuming you wear one) The down side is that it does take a bit of practice to stop the watch at the actual time.

Even after doing it for some time it is still easy to miss the time requested.

Personally I prefer Collectors workshop version although their's is a wrist watch it is much easier to control.

However saying that this looks good and a real mystery if done properly.