I'm excited! Just bought a Joule 1,100 W as a birthday present for myself. Haven't tried it yet...dealing with other stuff right now. But excited to try limoncello and tempering chocolate.
The key seems to be: massaging the vacuum package while it's in the water bath to ensure the tempering crystals are distributed evenly.
In the comments, those who know how to temper felt it was a waste of plastic vacuum bag and time. But I'm willing to give it a shot. I liked his idea of resealing the bag when done.
When I watched Claire Saffitz on BA creating various candy bar clones, she typically used this method to coat the bar.