Those pole or I guess Nike jacks can surprise you. A dozen years ago, I had the car up on one to remove tire chains on a mountainside, and the female threads gave way, much like a vise or spring compressor fails.

The wear factor: I was using them frequently at home before I owned a floor, floor jack, or bottle jack. I was not keeping them greased, and anyway they are not meant for anything more than emergency tire changes.

The scissors jacks that came with the later 240's never got this kind of use by me, so I can't help with the wear factor on them.
--
Art Benstein near Baltimore

Never pass up an opportunity to go to the bathroom.