Whats the best?

Have the hinged type now with the ball inside.

They are simple and work well. This is one of those open subjects. Float switches are gummed up by oil and crud and broken by stray equipment to the extent that it is difficult to keep tabs on the life of different kinds.
There is some discussion about 3 switches to a pump etc. but replacing both is never a bad idea.
Due to all the foreign production, you never know what you have this each time.

Anyone else?