Liberty Pump Switch Reliability

All this talk about Zoeller switches on M53 has me looking at the Liberty pumps.
Specifically, the mobel 257 has a float switch that is a VMF which appears
to be magnetic with a float. Any experience with the reliability of this
technology????

Also any opinion about 257 (cast iron housing) vs 237 (aluminum housing)??

I know this is a VERY old post, but now 10 years later does anyone have any opinions on this? (VMF switch and the aluminum vs cast iron)?

I've had excellent results using a HydroCheck HC6000 "Hi-Lo Sump Pump Controller" with a manual pump. No floats to hang up and no mechanical switches to go bad. There are two sensors so you can set the on/off height where it works best for your situation and to reduce short cycling.

I also use a Basepump water powered backup sump pump. If you are on public water and not on a well they work great.

I've installed a few Liberty model 230 pumps (manual, no switch) that are powder coated aluminum without any issues.
I hope this helps.
Jim