There are ways to over come that I have float valves to turn off the pumpI am not a fan of these type of overflows. In the event of power issues i do not want to dump water from sump on the floor due to over flow.
here is another instead of the skimmer you plug in your return pump and place the sensor where you need it.
i have a APEX works like a charm, I have a sensor in the sump and in the main display in case water gets too high in either one