IMHO - I would not rely on this as your primary switch. Electronic switches can fail for a variety of reasons including accumulation of scale. If this is the way you want to go, then make sure you keep it clean!
I prefer SJE Rhombus switches....either the vertical master or in some situations the double float switch if you are trying to maximize the length of the pumping cycle. Both feature a piggy back design so that you can still operate your pump manually if needed.