Several forum members swear by the SJE Rhombus Verticalmaster pump switch.
It looks like SJE has another product, the SJE D-master, which is another pump switch, but it is a non-tethered, pressure activated, diaphragm switch. it has 10" of travel, longer than the vertical master's 6.5".
Details on the SJE D-Master are here
Has anyone employed the SJE D-Master in a sump application? I'm removing an old, loud RIGID pedestal pump to be replaced by a submersible ABS Robusta, but I need a piggyback switch like the Verticalmaster or D-Master.