I've tried them all. Even the new electronic ones and none of them work worth a hoot over the long term. Well, maybe not so humble of an opinion on this subject. I've tried all the usual suspects and some not so usual and never was satisfied. Then I found the air switch and never looked back. I've had them installed for over 10 years and they have never failed to work. I have to say that I looked on line and my style is not made anymore but the new one's look pretty good. A couple of years ago I tried to install a float switch for my shower drain and finely gave up and installed an on off switch. I must have gone through 5 different kinds of switches and none of them were any good. I couldn't use an air switch because there wasn't a way to get the plastic tube up out of the pan. I highly recommend you try an air type switch the next time you need a switch in the bilge. All the wires are on a terminal board way up out of the water and all you have in the bilge is a small plastic tube. The water rises and compresses the air in the tube against a bellows and a switch is made up for the pump to run. Very simple.