Jason responded to Yvonne when in a recent Live Ask Jason Q&A session she inquired "What is the best choice for a second sous vide machine?"
A recommendation for a second sous vide circulator? I'd say same criteria as the first unit. Pick a circulator that has the type of functions that interests you. The Anova Nano is a great bare-bones one, and the Anova Precision cooker has the Wi-Fi and the Bluetooth. The Joule is more kind of fancy. If you tend to be a tech geek, the lack of physical controls on the Joule makes it fun to play around with!